If you just want to learn PS, and get a grasp around some of the "cooler" concepts in PS, check out the Photoshop WOW series. They are by Jack Davis. (Who is a great presenter, if you ever get a chance to go to one of his conferences.) After your done with that book, a more advanced book that gets into some more "practical" applications would be "Real World Photoshop 7". The name of the authors escapes me right now for some reason, I'm not at my desk. A combination of the two, with basic stuff aimed more at real world application would be the Visual Quickstart series. I can't remember that auther either. Oh yeah, The Photoshop 7 Bible is a great book as well, but I use it more of a reference as it is kind of advanced.