Online is the best way to learn things, at least for me it is (partly cause its free) 🙂
I strongly recommend going to a bookstore (Barnes and Noble) & browsing thru their books before buying one online.
I don’t have a book but I did a TON of research (weeks) trying to find the perfect book. I never ended up getting one of the detailed books, mostly because I’m really familiar with Photoshop so I can just google random things.
I learn best by picture examples and text, but I’m more of a visual learner than text.
This book, Photoshop CS: Essential Skills is supposed to be really good & highly recommended. I almost bought it, but I forget why I didn’t. Now I want to go back & see if its cause of the lack of pics examples or the price:
Also, this book looked good & reviews say its easy to understand (some photoshop books can be really confusing). I didn’t get it because most of it covered stuff I already knew how to do. If you don’t know too much about photoshop, this one seemed really good:
I bought this book because it has lots of pics & steps in pics & info on a few specific things I was trying to learn. If you know how to do basics, this one helps. It tells you how to do 100 things in photoshop. Its not meant to teach you the entire CS4 program, just how to do specific things in CS4, but I’m sure you’ll learn the program along the way!:
All the other photoshop books I saw there were too word heavy. There were pages & pages & pages of text with few pic examples. If you’re fine without examples, than you’ll probably have more options.
If you have any questions about CS4, feel free to PM me & I’ll do my best to help out 🙂