IMO, taking a class is a waste of time and a lot of money, unless you really, really struggle with discipline. And even if you do struggle with discipline, I'd still advise against a class. Hire a private tutor. You'll be shocked how little the cost difference is and in half the time, you can get 10x the personal attention to your specific problems.
My study method was to buy the Kaplan book, which has a really great interactive CD rom. It goes through all the basics and has a nice bunch of exersizes (and a great test-taking interface). Then, I bought a few books that have a bunch of tests and took a test almost every night for the 2 weeks prior to the LSAT, and the nights I didn't take a test, I did bunches of sections of Logic Games (because that was where I needed to focus and its the easiest section to improve on via practice).