It looks like most of the requirements in terms of door width, switch height, etc., are right on this web site:
www.access-board.gov/adaag/html/adaag.htm. The main ADA site is here:
www.usdoj.gov/crt/ada/adahom1.htm. It took about one second to google it. I'm not sure why anyone would need to pay for expensive books or consultants ...