The most important resources to help you study for the LSAT are real, genuine, LSAT questions. The simplest and cheapest way to get 30 real mostly modern LSATs are to buy the 10 Actual LSATS Volume V the Next 10 Actual LSATs and the 10 New Actual LSATs. These will provide you with enough questions to last you for some time.
The Powerscore books are also a helpful resource. Although we have some criticisms of them (which you can read here and here). The Powerscore books are also cheapest at Amazon and most people find the Logical Reasoning Bible and the Logic Games Bible to be most helpful.
Many other resources can help you both during your time studying for the LSAT and afterwards. LSAT Blog is known as a valuable resource, and Cambridge LSAT is also helpful, particularly when purchasing LSAT material.
Top Law Schools is another valuable resource, although we hesitate to recommend their LSAT forums. These forums seem to provide a lot of dubious advice, and it is impossible to know who you are getting your advice from. We do, however, highly recommend their law school and admissions forums which are extremely valuable. Law School Predictor is also helpful, as is the LSAC version of the same thing. Both are useful, but please remember that these are approximations and that numbers are not the only thing law schools look at.
If you are located in California and need a LSAT class or a tutor, we recommend Nathan Fox . If you have taken the LSAT and are in the law school application process (especially if you are located in NYC), we recommend Mary Jacobs at Apply Point Consulting.