The Magician's dictionary. Handy for all those complicated terms and jargon.http://www.neopagan.net/Pagan_Glossary.html
Alt.Religion is another encyclopedic site. Symbols and terminology are explained. Always handy.http://altreligion.about.com/od/symbols/Symbols.htm
A gem of a site, chock full of information.http://www.sacred-texts.com/index.htmEncyclopedia Mythica
The award-winning internet encyclopedia of mythology, folklore, and religion.The Arcane Archive
A cache of usenet and other text files pertaining to occult, mystical, and spiritual subjects.Gnosis.org
Everyone should learn a little Gnosticism. It promotes understanding. It has all manner of mysticism on it, Sufi too.