One of the things that continuously surprises me is just how few resources about user interface design are out there. Rather than include a huge bibliography that you may ignore, I've decided to include just six books, because I actually think you should go out and buy all of them. They are all that good.
Krug, Steve. Don't Make Me Think. Simon & Schuster Trade, 2000.
Laurel, Brenda (editor). The Art of Human-Computer Interface Design. Addison-Wesley, 1990.
Nielsen, Jakob. Designing Web Usability: The Practice of Simplicity. New Riders Publishing, 1999.
Norman, Donald. The Design of Everyday Things. Doubleday, 1990.
Tognazzini, Bruce. Tog on Interface. Addison-Wesley, 1992.
Tufte, Edward R. The Visual Display of Quantitative Information. Graphics Press, 1992.