I just finished reading the book "Don't Make Me Think" by Steve Kurg. It is a book on web acessablility and I would recommend it if you are in web designing. It is well written, witty and has very valid information on how do design so that the site may be easier to use.
There is one point I have to share here - people will not read something on the web if it is long - but if you manage to compress the same information into one small sentence, over 90% of you visitors will read it. Now, if I had followed my own advice, the last sentence will look like this...
Users love small sentences.
The next book I have to read is "Web Design Acessability" by Jacob Nielsen - much larger than "Don't Make me Think", but more detailed.