The Wikipedia article -- the informational links at the end are especially useful.
ASPEN -- the ASPerger Syndrome Education Network, with a particularly good recommended reading & viewing list.
Aspergia.com -- site for Aspies with a positive slant on the problem:
Re-branding Asperger's. Asperger's has never been a disability, but because the definitions sit with mental health professionals it is very difficult to see it as anything but a "problem". We ask: Is it possible that the Aspergian Mutation actually has a role to play in the greater scheme of human evolution? Is it possible that rather than a fluke, AS is a positive mutation gaining more gene real estate?