http://www.lgta.org/accessibility/

If you go to: http://www.lgta.org/accessibility/

you will find:

Web Site Accessibility
How to create, modify, and check your web pages
to make them "universally accessible" 

This site is structured like a class but is very self-directed.  
There does not appear to be any interaction - so more of a resource 
site.

Worth a look through.
The authors are:

Jeanne Wiebke, at jwiebke@iastate.edu at Iowa State University
Linda Ffolliott, at ffolinda@ag.arizona.edu at the University of 
Arizona 

My apologies if this site has already been mentioned.

Gretchen