Terminator,
Check out my post above you. The Kaplan 800 book is ok to get you started, but remember the math is not NEARLY as hard as you need to get Q46 or above. Once you have mastered the Kaplan 800 and
OG you need to get the Manhattan Number Properties book, then after you master that, just buy the
GMATClub tests. They will really bring your quant score up. Again, all this in conjunction with
the Official Guide. Also, for verbal use the Manhattan Sentence Correction guide, Powerscore LSAT Logical Reasoning Bible for CR, and maybe Manhattan Reading Comprehension Guide. For this, you need a good problem set of RC questions - one that will just give you reading practice. I took a Kaplan class last year, although not the Premier, and I would also look into Manhattan if you MUST take a course. They both will give you a good base to get started - its just that its $1300 bucks, dang.
Again, I am a joe blow, and I am not afilliated with any of these companies I named. I have just ran the gauntlet so to speak.