2010 Standards for Accessible Design - U. S. Department of Justice

Design for Accessibility: A Cultural Administrators Handbook
The goal of "Design for Accessibility: A Cultural Administrator's Handbook" is to provide guidance to cultural administrators on accessibility and inclusion for creating new or opening up existing programs to include individuals with disabilities and older adults, whether as staff, volunteers, program participants or audience members. 

Web Accessibility Toolkit - Association of Research Librarie (ARL)
Though specifically geared toward research libraries, this toolkit provides excellent information libraries of all types.

Accessibility Resources - University of Michigan Information and Technology Services

Web Accessibility Evaluation Tools List - W3C
Web accessibility evaluation tools are software programs or online services 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.