Don't Make Me Think!

The best reference I can suggest for usability and accessibility philosophy is Steve Krug's book, "Don't Make Me Think."

Google it or look it up on Amazon. You can pick it up used for not much money. 

http://www.sensible.com/

Steve has a sense of humor and if you can develop your intuition to include his philosophy, you will be well on the way to understanding your users and how to design websites for them.

Look him up!