Web Accessibility Google
Google have launched customised search engines via Google Co-op, a new (beta of course) corner of the Google empire.
It's a potentially powerful tool. Here's a quick web acessibility search engine I setup to test it:
It's restricting searches to just 4 domains, and yet produces pretty decent results for any accessibility issue you care to throw at it. With a bit of time, care and attention it's going to be possible to create fantastically targetted search engines. Even better there's a community element, since anyone can suggest sites to add to the search engine, and if the engine owner deems them suitable they can be easily added.
Throw some accessibility-related terms at it and see how it fares. And if you've got suggestions for sites to add to the list just follow the 'Volunteer to contribute to this search engine' link (if you've got a Google account) and do your stuff.
You can also access this engine at its homepage.