Mushrooms, cacti, Hawaiian baby woodrose seeds, nutmeg, and datura.
http://www.stainblue.com/ah.html
About Dr. Albert Hofmann, who first synthesized LSD. Includes chemical information and diagrams.
http://www.hofmann.org/
Homepage of the inventor of LSD. Contains articles, information about projects, reviews, and a virtual museum tour.
http://www.psychedelic-library.org/
Menu of articles, research papers, books, and essays on LSD, peyote, psilocybin, and the use of psychedelic drugs in research, therapy, religion and personal growth.
http://www.shroomery.org/
Includes information about psychedelic mushrooms, including cultivation.
http://www.tripzine.com/
A mainstream publication for about psychedelics.
http://en.wikipedia.org/wiki/Salvia_divinorum
Open encyclopedia article covering the history, botany, legality and chemistry of Salvia.
http://www.yahooka.com
Includes a guide to marijuana information and sites, also free email accounts and discussion forums.
http://www.peyote.org/
The divine cactus in historical context.
http://www.ambitiousaddict.com/
Discussion forum, photos, and user contributions.
http://www.cognitiveliberty.org/shulgin/
Information about psychedelics, entheogens, empathogens (MDMA, Ecstasy), from a pharmacologist and chemist.