The following is a list of websites with good information about accessibility. Some features in google sites can be tweaked for good accessibility with a little work. Check out my comments about each site.
#1 - Various tips to help authors create accessible World Wide Web documents. ... Accessibility Tips. Validation. Platform Independence. Structural HTML.
Comments: nice easy site to follow and understand
#2 - Authoring Tool Accessibility Guidelines 2.0 Working Draft 21 May 2009 ... Web Accessibility for Older Users:
Comments: the home of accessibility standards, information overload.
#3 - WAVE is a free web accessibility evaluation tool provided by WebAIM. It is used to aid humans in the web accessibility evaluation process. Rather than providing a complex technical report, WAVE shows the original web page with embedded icons and indicators that reveal the accessibility of that page.
Comments: great little tool for checking accessibility, i use the firefox addon to check my sites.