I am really interested in getting a good laptop for gaming, but definitely would need it to be under $1000. I play mostly FPS games like Left4Dead, Quake 4, etc. and will be looking forward to Starcraft 2. I'm not sure which brand laptops to look for and which ones are the best value. I just want to get the most bang for my buck.
Under 1k for a gaming laptop is going to be hard. The best bang for your buck lives between 1150 and 1350....
But, the Asus G50vt-X1 and G50vt-X5 are around your 1k price cap, and would do well with the 9800m GS. The differences being the X5 has a bigger battery, and the X1 has a slightly faster CPU.
-That's my best recommendation if you need to stay under 1k. (you'll barely go over with tax).
If you're willing to pay a tad extra the MSI GT627-216US @1099, and Gateway FX P-7805u @1,115, are nice options. The MSI being nice and sleek, weighing in just under 6 pounds. The Gateway has a nice 17" display and 9800m GTS 1GB, but... is kinda bulky.
In the under 1300 price range you'll end up with a low res display (unless you go Gateway), with meh black quality and contrast.... which isn't an ideal situation for a game like Left4Dead. If you can come up with a few hundred more, there are some really nice options between 1300 and 1400. (G50vt-X6, GT627-218US, MSI GT725-074US)
If you decide to go cheap Asus, and you like the G50vt-X1 more than the G50vt-X5, I would get on it quick. Since Best Buy has already started to replace the X1 and at 950 bucks its selling pretty fast.