General AIDS information
AIDS info
http://www.aidsinfo.nih.gov
US Government sponsored portal with links to treatment guidelines and clinical trials (see below).
HIV InSite
http://hivinsite.ucsf.edu
A project of the University of California, San Francisco AIDS Program at San Francisco General Hospital and the UCSF Center for AIDS Prevention Studies. This is a comprehensive website for HIV and AIDS. This site also contains the AIDS Knowledge Base: an electronic textbook on AIDS and HIV that is frequently updated, with summaries of recent research on HIV and AIDS.
Johns Hopkins University AIDS Service
http://www.hopkins-aids.edu/
A wide-ranging collection of resources from Johns Hopkins University. Includes treatment updates, guidelines, plus full text of the AIDS handbook, Medical Management of HIV Infection, as well as a bimonthly newsletter, The Hopkins HIV Report.
Division of AIDS, National Institute of Allergy and Infectious Diseases, National Institutes of Health
http://www.niaid.nih.gov/daids/
Links to treatment and prevention information, publications and meetings; vaccine, prevention, and treatment networks, and the Comprehensive International Program of Research on AIDS (CIPRA). Funding opportunities for both United States and international investigators, including those in poor countries with large HIV burdens.
United States Centers for Disease Control and Prevention
http://www.cdc.gov/
The CDCs website and its HIV homepage http://www.cdc.gov/hiv/dhap.htm, the definitive US source for epidemiologic information, downloadable publications and slide sets.
(Note: The manufacturers of antiretrovirals, HIV diagnostics, and agents for AIDS-related opportunistic infections maintain websites with information pertaining to their products. These are often country specific, but can generally be easily found using the popular search engines.