I have a good flash and use it from time to time. Sometimes I am pleased with the results, but often I know it could be done better. I don't feel that I am up to speed enough on flash photography. A big part of the reason is that I just don't do that much of it, but I'd like at least have a much better understanding.
Does anyone have any books/resources/references they could recommend to get the most out of my flash. I am not interested in studio lighting with umbrellas, strobes, etc. I have a 7D, a 580EXII, and a diffuser. I am looking forward to playing with getting the flash off the camera now that I have the 7D with the wireless.

