What score did you receive on the practice test? And what practice test did you take? (Barron's? Kaplan? PowerPrep?) I would recommend, if you haven't already, download the free PowerPrep software from ETS and taking the first CAT simulation practice test. Use that score to gauge your weaknesses.
My major weakness was quantitative, after failing most rudimentary math courses through my entire high school career - and Barron's has been invaluable. Do the Math Review and as many practice questions as possible to both polish your skills and get into the mindset of "GRE Math" which is a fairly unique animal. Most problems will not require you to solve them "brute force" through protracted, painful calculations but to identify some sort of shortcut or trick within the numbers provided.
Honestly, if I had to recommend one GRE prep book, it would be Barron's. The word lists - both the "hit parade" of high frequency vocabulary, and extensive alphabetical or themed word lists will be incredibly helpful to you if you're studying on a tight schedule. The quantitative review was excellent - dividing the sections into specific question types (Quantitative Comparison, Data Interp, etc) or by type of math (geometry, number theory, probability, etc). The practice tests that come with Barron's, however, are not the best reflection of the actual exam (as far as I know) but that is what the PowerPrep software is for.
I take the GRE in 3 days, and of the $200 I spent on various GRE materials, I wish that I only bought the Barron's book. Take my advice with a grain of salt, however - I can't be 100% certain how prepared I am until I take this damn thing. I'll post an update once I finish the exam with additional thoughts.