I was never a Photoshop expert, but I got to the point where I was able to do quite a few fancy things with it quickly and easily. I attribute this in no small part to major advances in Photoshop's user interface over many well-tested versions, as well as good on-board documentation. Of course, now I'm trying to learn how to use Gimp, the Open Source equivalent. Despite the fact that many seem to love this program, I'm finding it difficult to do anything more than a few basic tasks. I imagine this is what Photoshop might have been like in its earlier versions, when cutting off someone's head and putting it on someone else's body involved skilled manipulations of masks and channels.

A bunch of books are available on the subject, both in print and online. The Gimp Manual appears to be semi-official, and is available online or from Coriolis. Its many examples are inspiring, and feel like good starting points for experimentation. Amazon customer reviewers hate it because it dashes over actual instruction to favor demonstrating the program's power, which so far seems true. Grokking the GIMP, full text and figures online and in print from New Riders, does a pretty good job covering basics and discussing theory and technique, but I find myself begging for step-by-step screenshots even simpler than it provides. It fairs much better in the Amazon customer reviews. A problem common to both books, or at least their online versions, is that I can't tell which version of Gimp is used in the examples, so when theirs doesn't look like mine, I can't tell if I'm not looking for the button in the right place or if the button moved. Maybe I'll have better luck with these tutorials...