ba11yhoo: a Big Accessibility Hierarchy, Opportunistically Organized

This page has a rather grand name. Actually it's just a list-of-lists about digital accessibility.

Accessibility Information Pages and Contact Pages

Lots of organizations explain the accessibility of their web sites and products, and offer specialized contact channels for accessibility. Here are some notable ones.

• List of Accessibility Information Pages - Law Office of Lainey Feingold

Accessibility Style Guides and Design Patterns

• List of Accessibility Style Guides and Design Patterns

Assistive Technologies

• Assistive technology - Wikipedia
• List of screen readers - Wikipedia

Assistive Technology User Surveys

• List of Assistive Technology User Surveys

Digital Accessibility Conferences

• List of Digital Accessibility Conferences and Archives

Digital Accessibility Consultants

I haven't found a good list yet. This one is independent, but as of 2017 it's incomplete.

• Accessibility Companies and Consultants - DMOZ

Digital Accessibility and Law

• List of Web Accessibility-Related Litigation and Settlements - Karl Groves

Digital Accessibility Testing Tools

• Web Accessibility Evaluation Tools List - W3C Web Accessibility Initiative