I did nothing other than read "Law School Confidential." I'm really glad I didn't. If you feel like you must do something, the wikipedia articles about the general subjects that someone else suggested should be more than sufficient.
The only thing I wish I'd read before school started was "Guerila Tactings to Getting the Legal Job of Your Dreams." Anything else would have been a waste of time, at least for me.
In my experience, the stuff you learn in class is what's on the exam, not the stuff out of E&E. If you pay attention to the prof and her or his hypos, you'll know what's coming. It might not be like that at every school, but it certainly is at mine.