The Denying AIDS blog has a link to a good article on the anti-science of AIDS denialsim.
[T]here is another camp of deniers festering away in the underbelly of alternative medicine. These people are the AIDS deniers; people who claim that AIDS is not caused by the HIV virus, but rather that it is actually caused by drug use. Some even go so far as to claim that HIV does not exist! Given the horrifying prevalence of AIDS in third world nations and even its alarming proliferation in developed nations, increasing support for AIDS denialism is not simply worrying but outright dangerous.
The article is from C.W.G.K’s blog.