W3.org: Web Evaluation Tools List -- Web accessibility evaluation tools that help you determine if web content meets accessibility guidelines. This page provides a list of evaluation tools that you can filter to find ones that match your particular needs.
WAVE--Helps you check if your page is accessible to people with disabilities. Wave is commercial product and can be used to check multiple pages or a whole website.
Accessibility: World Wide Web Consortium (W3C) --The W3C is the international standards-setting organization for the World Wide Web. As such, it has issued comprehensive standards that ensure an accessible web presence known as the Web Content Accessibility Guidelines (WCAG).