Mostly self taught via trial and error error error error...error.

But also one of the best learning sources is the Digital Camera Magazine, the English version available every month from most newsagents. Apart from inspiring images to get your creative juices flowing every edition comes with an instructional CD covering all aspects of most PS programs all in easy to comprehend step by step instructions, as well as step by step instructions in print as well. Features more advanced instruction and simple to at least get you over initial hurdles.

A whole lot cheaper than paying someone to educate you, and a keepable reference library of CD's to refer back to at any time.