Drug Research Project
A search engine that links you to government produced information on a wide range of health topics.
National Institute on Drug Abuse
This organization created an online series called "Mind Over Matter" about different classes of drugs. You will also find extensive information in the form of research reports, news releases, recent articles from their newsletter and much more.
Full of gloss and glitter, this site from the Office of National Drug Control Policy is fun to use and informative.
A searchable online dictionary to street slang terms for hundreds of different drugs.