To do ritual, you would generally use ritual tools. These tools aren't necessarily things like the pretty glass wand wrapped up in your drawer - you might use a twig from a handy tree instead. Most of the time, though, we're prepared enough that we've got a selection of tools for specific functions within the ritual. For a lot of Witches, these tools are ritual tools only - once they have been consecrated and charged, they are never used for mundane purposes again (you won't find their ritual knife, for example, chopping carrots in the kitchen). But, for some people (kitchen Witches especially), the fact that the knife is a central part of the preparation of the family meal makes it even more important in ritual. Yet another example of the diversity within Wicca.
Athame (also athamè)
An athame (pronounced 'ath-a-may', with 'a' as in 'above') is traditionally a double-edged, pointed blade about 15cm long with a black handle that sometimes has symbols and glyphs carved on/set into it. The blade is conventionally dull, because the athame is used for working with energy1, not for slicing up physical objects - because it doesn't need to be sharp, the blade of your athame can be made from things like pewter, bone or wood. The athame is associated with masculine energy, and is often used as a phallic symbol within a ritual and to represent the male in the symbolic Great Rite.
We don't know where or how the athame originated, or even really where the word came from. The athame was apparently a favourite tool of Gerald Gardener (who was a collector of and expert on antique swords and knives), and Gardner is said to have coined 'athame' from a modern French translation of a grimoire (a Medieval book of magic, not a Book of Shadows as we think of it) called the Key of Solomon. In a 16th-century Latin version of this manuscript there is a drawing of a curved ritual knife called the artauo2 (picture below), which was later translated to French as arthane or arthame. 'Athame' is also similar to the French attame, meaning 'to pierce' or 'to cut' ('to pierce' seems to be the more accurate translation), so this seems like a reasonably likely scenario.
It seems that the athame is peculiar to Gardnerian tradition - that is, it has been 'passed on' to all other modern trads that came after it (remember that Gerald Gardner basically 'founded' modern Wicca). Ceremonial knives were not a feature of British pagan practices before the 1960's Wiccan revival, for example - they came into British Witchcraft through the Gardner. He's not called the 'Father of Modern Wicca' for nothing.
Besom (broom)
A besom is not the same as the broom you'd use to sweep the kitchen floor - a Witch's broom is used to sweep negativity from the ritual space. While sweeping the ritual space, the bristles don't need to touch the ground - the sweeping is symbolic, and accompanied by visualising the negative energy being swept from the space. Generally, the besom is made of twigs/straw/herbs tied onto a larger piece of wood that serves as the broomstick. What wood your broom is made out of is basically up to you - I've read that traditional brooms were made from birch bristles tied onto an ash handle, but I'm not sure how accurate that is. If you're interested in making a 'traditional' Witch's broom, there's a great website with detailed instructions that might be of interest.
The broom probably became associated with Witches during the persecution of 'Witches' (in and around the Burning Times) - because the broom was a common household item, any actual Witches using it as a ritual tool probably didn't look all that suspicious. Finally, a couple of interesting facts - during handfasting ceremonies, the couple traditionally jump over a broom; and a broom with upturned bristles hung over or near a doorway apparently protects the house from negativity.
Bolline (also boline, bolleen)
A bolline is traditionally a white-handled, curved knife with a single sharp edge used for cutting physical things during ritual, such as cord and herbs, or for engraving candles - whatever needs cutting within the ritual is cut with the bolline. The vast majority of bollines out there are crescent-shaped, but straight-blade bollines do exist - it depends which form you like better.
Candles
Candles are multi-purpose objects - red, blue, yellow and green ones can represent the elements at the four compass points within the magick circle, gold and silver candles can represent the God and Goddess on your altar, or they can simply be your source of light. Candles also come in some useful shapes - if you were doing a love spell that called for a red candle, for example, you might get lucky and find a heart-shaped one! Or, if you're feeling creative, making your own candles isn't hard (it's fun, too).
Censer (also brazier, thurible)
A censer is a vessel for burning incense. The most common form people tend to think of is the pierced ball on the end of the chain that priests walk up and down church aisles with, but your censer could be anything from a bowl of sand to hold incense sticks and catch the ash to an ornate pierced vessel like the priest's. My favourite censer is a hollow plaster dragon with holes at the nostrils and around the base for the smoke to get out - it looks great with lit self-burning cones inside it! To go with your censer, obviously, you'll need incense - this might be the self-burning incense sticks/cones we're all familiar with, or the ground herbal incense that needs smouldering charcoal to burn.
Cauldron
The classic Witch's tool! In fiction, Witches prepare a cauldron-ful of smoky, noxious-looking brew and then use only a tiny vial of the stuff to suck the life out of some unsuspecting child (à la Hocus Pocus). In the real world, the cauldron is generally made of black cast iron, with three legs and a semi-circular handle, and is a symbol of abundance, regeneration and prosperity, and represents the womb of the Goddess. The cauldron comes to us from Celtic mythology, where it is associated with Cerridwen and provides nourishment, inspiration and even raises slain warriors from the dead. It can be any size, from four inches to four feet, and can be used in a variety of ways - to hold items for burning in ritual, filled with water for scrying, or filled with lit candles to create the illusion of a fire. It is usually placed in the centre of a magick circle.
Chalice
The chalice (or cup, or goblet) is used for drinking during ritual, and also as a symbol of the female in the symbolic Great Rite. It's kind of a miniature version of the cauldron, in that it is very closely associated with female energy and regeneration. Chalices are generally round and, well, chalice shaped - a wine glass-type shape, for lack of a better description - but you could have any thing from a simple pottery cup (like Indiana Jones and the The Last Crusade) to a fine crystal goblet. Chalices are often made from metal (stainless steel, silver, silver plate, gilded metal and so on), but my favourite chalice is a fine glass one with a silver rim that I came across by chance a few years ago (it looks great in candlelight). You'll probably find a chalice at some point that you just fall in love with and have to have - pick one that's right for you and feels like a good fit.
Elements
It's also important to have something to represent each of the four elements in your circle - especially if you'll be consecrating something. You might use salt or sand for Earth, a feather or incense for Air, consecrated water for Water, and a candle for Fire. You get the picture.
God/Goddess images/symbols
When you're doing any kind of ritual or magick, it's important that you have something representing the God and Goddess on your altar. These things are any objects that you associate with the Divine - perhaps actual statues/drawings/images of a God and Goddess, or gold and silver candles, or even something like shells, seeds or flowers. If you're looking for some images of Gods and Goddesses, I've compiled some image galleries you might find helpful (it'll save you trawling though Google image searches).
Scourge
This is a slightly controversial ritual tool. The scourge, basically, is a ritual whip. It isn't intended to do any physical damage, and it usually comprised of a wooden handle to which eight thongs of silk or thin cord, each with five knots, are attached. The purpose of the scourge is a little sketchy to those of us outside one of the Gardnerian covens that still use it, but the idea is that the scourge is used for ritual (symbolic) purification and as a symbol of spiritual discipline. It's most useful in a coven.
Wand
Another famous Witch's tool. The wand is another symbol of male energy, and is used to direct energy in the magick circle. Your wand might be a piece of driftwood you found at the beach, or an ornate glass-and-gem piece you found at your local metaphysical shop. Mine is an unfinished, thin piece of plain willow that I dried, stripped the bark from and sanded the sharp bits off, with a piece of clear quartz bound to the end (it took a little effort to make!). For those of you that don't like knives, the wand can be substituted for an athame.
Finding ritual tools isn't difficult, really. If you can't find it in a local shop - make sure you look around the op shop as well as the metaphysical one - I can just about guarantee you'll find it on eBay or in an online shop somewhere. The golden rule of buying ritual tools is: don't haggle over the price. It's a difficult concept to explain, but haggling 'cheapens' the tool, and lessens its value. Ritual tools are beyond ephemeral things like pricing. If it's worth the money, then buy it - if not, leave it. You might even find you don't need to buy a lot of things - there may be a nice old pewter chalice in a dusty box in the top of the cupboard, for example. Go on a treasure hunt before you go shopping!
Remember that you don't have to have all the accessories to do ritual - if you want to, you can cast your circle with your finger. Don't spend all kinds of money on tools you don't need all at once - collect them over time. And don't let anyone tell you that you must have that rather overpriced item on that shelf over there or your ritual won't work - that's a clear signal that you need to shop elsewhere.
Before you use your new ritual tools
Before you use your new tools, you need to consecrate them. You need to make sure that only the energy you want is present in your equipment, so you don't 'contaminate' any energy you raise in ritual with dirty tools. Some people only consecrate their tools before their first use, others 'freshen' their tools every year, and some re-consecrate their tools every time they use them - there is a point at which this becomes almost obsessive, but by the same token you need to be comfortable with your tools. If you want to keep your tools 'fresh' after you first consecrate them, then you might like to try keeping them in a black box or wrapped in a black cloth (because black repels negativity).
Storing ritual tools
Storing your ritual tools only takes a little common sense, but is also pretty important. You don't want them collecting dust - literally or metaphysically - and, similarly, you don't want the family dog chewing on your broom. You might like to keep your smaller tools in a drawer, or in a box in the bottom of your wardrobe - the wardrobe is also a good spot for your broom. Make sure that when you put your tools away you haven't left candle wax or anything on them - you wouldn't put a dirty knife back in the kitchen drawer, would you? And, if there are nosy people in your house, you may want to make your tools difficult to find - you don't want just anyone handling your nicely consecrated ritual tools.
1. Witchcraft Today, Gerald Gardner (1954), p. 13, 33.
2. The Key of Solomon, edited by S. Liddell MacGregor Mathers (1889), Chapter VIII.