Section 508 Guidelines
The federal Access Board 508 Web-based explanations page
Lengthy descriptions of each rule with examples
WebAIM Section 508 Checklist
Explanation of each 508 rule with descriptions of how a site will pass or fail the rule
JimThatcher.com has a section on Web Accessibility for Section 508
More detailed descriptions of each rule with numerous examples
Accessibility Testing Sites and Tools
Accessibility Testing Toolbars
WAVE Toolbar for Chrome
Deque aXe Extension for Chrome
Deque aXe Extension for Firefox
Web Accessibility Toolbar for Internet Explorer
Web Developer Toolbar for Firefox - adds various Web developer tools that help with accessibility checking
Accessibility Test Sites
WAVE Accessibility page for testing for compliance. Enter your URL into a field on this page and run test.
Firefox Accessibility Extender - download and install into Firefox to test accessibility of dynamically generated Web pages.
Fangs - download and install into Firefox. A tool that creates a textual representation of a Web page as it is read from a screen reader.
Color Testing Sites
WebAim Color Contrast Checker - test foreground and background colors by entering hexidecimal codes.
Colorblind Web Page Filter - enter a URL into this page and choose a filter to show how the page looks with various visual impairments.
Color Contrast Check - specify a foreground and background color either by entering hexidecimal codes or using red, green and blue sliders to create colors. Run a check on the colors to see if there is sufficient contrast.
Color Testing Tools
Colour Contrast Analyser - download and install to run color tests .
Helpful Sites on Web Accessibility
W3C Web Content Accessibility Guidelines 1.0, Web Accessibility Initiative info