I agree with Rob. After talking to current 1L's, I have yet to meet anyone who says Law Preview or other prep courses are worth it. Most schools do an orientation that covers a lot of what those courses cover - but for free!
Some schools have a suggest reading list, but it's not really anything to freak you out. Just some stuff to get you in the legal mindset, and also because once school starts, you probably won't read for fun for another 3 years. Here's a list Alabama provides: http://www.law.ua.edu/prospective/index.php?re=readinglist
. It's got everything from a biography of a SCOTUS judge to Getting Past No.
I've also heard read/watch entertaining law books/movies to get you in the mood for law school.
Mainly though, people say in order to prep for law school, you should:
2. pay down as much debt as possible, work a 2nd job if you have to
3. relax some more if your debts are paid down
4. move to your new city early
5. buy your books early