DanceSafe
North American organization promoting health and safety in dance community in a harm reduction model.
http://www.dancesafe.org/

Drug Line
24 hour drug detox/counseling referral
(415) 362-3400

Erowid
A non-profit organization “documenting the complex relationship between humans and psychoactives”.
http://www.erowid.org/

San Francisco Syringe/Needle Exchange Sites
(415) 241-5100
http://www.sfaf.org/hpp/sites.html

Sexual Pharmacology: Drugs That Affect Sexual Functioning by Theresa L. Crenshaw, M.D. & James P. Goldberg, published by W. W. Norton & Company [Buy]
Detailed reference book for doctors and therapists about the positive and negative effects on sexual function for both prescription drugs and abused substances.
ISBN 0393701441