The following links offer significant data for students and instructors with special needs.

Visually Impaired

http://www.microsoft.com/enable/training/guides.htm
http://www.trace.wisc.edu/docs/quick_sheets/qs6.html
http://www.brailleinstitute.org/
http://www.aph.org/

Learning Impaired

http://www.microsoft.com/enable/training/guides.htm
http://www.ldonline.org/
http://www.ldanatl.org/

Hearing Impaired

http://www.microsoft.com/enable/training/guides.htm