Hi bosho1,
6 hours a week of study time isn't very much; you would likely need to commit to at least 15-20 hours of quality study time each week for at least the next 3 months to properly train to consistently score at a higher level. If you meant to type 6 hours per DAY, then that type of volume is probably not necessary (and studying that much would likely increase your chances of 'burning out' - which is something that we want to avoid).
When it comes to studying for the GMAT, there are a variety of different options. Most GMAT Companies offer some type of free materials (practice problems, Trial Accounts, videos, etc.) that you can use to 'test out' a product before you buy it. We have a variety of those resources at our website (
www.empowergmat.com). I suggest that you take advantage of all of them then choose the one that best matches your personality, timeline and budget.
If you have any additional questions, then you can feel free to contact me directly.
GMAT assassins aren't born, they're made,
Rich