In case you have noticed, I added an Amazon widget on my blog. It contains and will only contain books that I own and have read (for the most part - some don't lend themselves to straight reads - more like references). The first book I will point out is "The Photographer's Eye" by Michael Freeman. Its an excellent book on composition and touches on some areas not often discussed - the shape of your image (the frame) for one. Personally I have felt that second to developing an eye for light, is the development of an eye for composition.
Blog image: nice morning shot of Mount Hood on a misty fall morning. Illustrates the compositional technique of layering or repetition.