Accessibility website evaluation with Firefox Web Developer or Accessibility Extension Tool Bars

Tools for anyone interested in accessibility when testing websites. Toolbars are not an automated testing tool so some manual work is required from you.

Mozilla Accessibility Extension
This extension provides many tools for both web developers and end users.

Features include:

Firefox Add-ons - Web Developer Toolbar
This extension helps in the development of accessible and standards-compliant web content. This toolbar provides more options than are listed here. This is an indispensable tool for web developers. Beyond the wealth of options of HTML and CSS code development features, the toolbar provides the following functionality to support accessible web development and evaluation:

For more information:

Gez Lemon's Table Inspector

WebAIM articles 
Accessibility Evaluation Tools article
- Quick Reference: Testing Web Content for Accessibility article