This handy blog site has a tab with all the neat new things you can do with CSS3, with visual examples where appropriate. In addition to this, there’s a great tester page which will check compatibility of your current browser against CSS3 selectors. When I checked, Firefox, Opera and Chrome all passed with flying colours.
Getting your head around the box model for CSS can be a bit of a mind-bending exercise for many people. Just try to explain it to a friend who doesn’t already know much about it, and you’ll see what I mean. Its not that its a difficult concept to grasp, its just very fiddly to