My friend Don McAllister sells a wonderful series of Apps based on his popular ScreenCastsOnline series that cover the basics of how to use a Mac, iPad, OS X Lion and iPhoto for iOS. The longer tutorials are usually around 2-3 hours and cost about $4 ($0.99 introductory price for the iPhoto for iOS version).
Don's excellent video tutorials and are an absolute steal at $4. For free, this is an absolute no-brainer. If you're a recent Mac switcher or especially if you have a friend or loved one who is new to the Mac or needs a little TLC give them Don's excellent Apps. I've gifted them to all my family members and I believe they've truly saved me hours of tech support!
Here's the link to Don's site were you can find out more about all of his Apps: http://www.screencastsonline.com/appstore/