For learning the Mac, go to
Apple's support page and look at the bottom left side of the page under the heading of solutions. The switch 101 is a good site, especially the Mac cheat sheet.
Also if you subscribe to
.Mac (maybe if you don't, so try the link) there is the Learning Center. Once again the focus is on Apple's products but videos are good.
Regarding books it really depends on type of person you are and what programs/topics you want. For Photoshop, I personally prefer books by Scott Kelby as they are more about how to do some particular task, instead of how to use the program.