Here are some good reads about food photography which have helped me in trying to improve my photography skills:
Desserts for breakfast – About the different styles within food photography, complete with a case study.
6bittersweets – Good read about how we don’t start out as great food photographers but get there through practice. Also some good advice concerning props.
Wright Food – Good tips about lighting and lenses.
Photoble – Ten quick rules to help you get along with food photography.