The technical definition of "occult" is:
"Of or relating to the supernatural, mystical, or magical beliefs of phenomena."
Essentially, the term occult can be applied to the encompassing beliefs of witchcraft, paganism, animism, and whatever else may go along with these.
There are no supplies that are technically needed, however candles, herbs, knives, athames, brooms, bells, and various shapes or effigies are commonly used. I'm going to assume that more information can be found in the beginner's section and possibly the FAQ section of the website.