How to Judge a Website's Accessibility Level
http://www.techdis.ac.uk/resources/dsloan01.html

Sloan, David
TechDis
2000

Abstract:

Many web developers and administrators are conscious of the need to ensure that their web sites reach as high a level of accessibility as possible. But how do you actually find out whether a site has accessibility problems? Certainly, you can not assume that if no complaints have been received through the site feedback facility (assuming you have one), there are no problems. Many people affected by accessibility problems will just give up and go somewhere else. So you must be proactive in rooting out any problems as soon as possible. Fortunately, there are a number of handy ways to help you get an idea of the level of accessibility of the site, which do not require an in-depth understanding of web design or accessibility issues. It may be impractical to test every page, but try to make sure you check the Home page plus as many high traffic pages as possible.