EIFL has released the FOSS Accessibility Tools for Libraries: Step-by-Step Guide.
Here's an excerpt from the announcement:
Using technology appropriately can enhance the library experience for all users, but is particularly significant for users with disabilities. Creating electronic resources as accessibly as possible is a useful starting point, but for some users specific technologies will be needed to access those resources. There are many FOSS tools available to support library users with a variety of needs, ranging from those with visual impairment or blindness, to users with dyslexia or who have difficulty using a mouse, or simply users who have limited reading ability or prefer to listen to text than read it on-screen. Most librarians are not specialists in this area and can be discouraged by the sheer number and variety of FOSS tools available to support disabled users. This is why EIFL have created a step-by-step guide to some of the most helpful and easy-to-use tools.