Cauldron - a bucket, a large pot from the kitchen
Wand - Harvesting your own wand is always prefered, just remember that when you harvest a wand you must give something back to nature in return.
Tarot cards - can be made by you yourself, and is actually some what prefered by many tarot readers as the tarot deck becomes specific to you and you alone.
Athame - a knife from the kitchen with a straight blade, a pocket knife, or is neither is available, you can use your index finger and middle finger together.
Scrying mirror- a simple hand mirror works just fine
Scrying bowl - a dark colored bowl from the kitchen, or one that you get cheap and then paint a dark color( usually black or brown)
Herbs in general - can be bought from the local grocery store
Runes - can be made by you, you can use dried out chicken bones, rocks you find, or even reinforced paper cubes.
Fine stones/semi precious - usually aren't to bad on price but when it's an issue, using stones you like that you find on a beach or in a rock pile work just as well.
Candles- also usually not to bad on price, usually 25cents to a dollar in most cases, when an issue, t-lights are just as good for representation of white, and now come in a wide variety of colors so take your pick
Altar- a milk crate, coffee table, end table, night stand, anything that is flat.
Altar cloth- simple fabric big enough to cover the surface being used as the altar. It is also a good idea to decorate it with symbols that mean something special to you.
When all else fails, remember - MAGIC IS ALL IN THE MIND, ALL THESE THINGS CAN BE CREATED IN YOUR MIND. Rituals can be done in the mind as well, just imagine all the tools and supplies on an altar, then preform the ritual in your 3rd eye.