I agree with Charles. Just dive into the app. I'm a NAPP member (
www.photoshopuser.com) and subscribe to Kelbytraining.com. Both are fantastic resources that are well worth the $$. My suggestion is to go month-to-month with Kelbytraining.com. If you have the time, you can run through most of the PS stuff in under a month. You can always go back and re-activate your account if you see something new come up. Things are a little slow on both sites right now as Photoshop World is the first week in April--that's THE big NAPP conference. If you really want to jump in, PM me and I'll be glad to share the resources I know of and my experience. Good luck.