As a supplement to any test prep book you get I think purchasing LSAC's 10 actual preptests (and then the 10 NEW ones and the ones with comparative reading) is invaluable to true test preparation.Since they are the closest thing to the actual test you can get your hands on, you can go through them as if you're taking the real test 10 times. The only problem is they do not provide reasons for the right answers, but most of the time I am able to work out where I went wrong and if I cannot I can ask for help (like I did in another topic in this forum, though people seem reluctant to respond).
Just make sure not to get stuck trying to learn and master techniques that may not work for you.