Ok .. .first things first ... if you want a notebook that is capable of gaming, FORGET ones that have integrated gpus (this includes Intel graphic cards, entry level Nvidia and ATI cards).
You need to look into mid-range or high range gpu's (ones that come with at least GDDR/DDR3 or GDDR5 Vram).
Amount of RAM on the gpu's is often misleading (a gimmick to fool people into thinking they are getting something 'great', when in fact they aren't) because 512Mb (maybe 1GB) is more than enough.
In fact, high-end gpu's cannot really utilize over 1GB video ram effectively (plus sometimes it slows things down to try and get to 1GB).
Mid-range gpu's will limit out at 512Mb (even less so in numerous situations due to bandwidth limitations - similar with high end gpu's).
Ok ... getting back on track:
I would recommend focusing on laptops with ATI mid/high-range gpu's because their newest generation (5xxx series) is better compared to what Nvidia has out (although various Nvidia solutions aren't bad, they DO require of you to be well informed because they purposefully rename/rebadge their gpu's in a horrible naming scheme that throws people off, plus laptops with Nvidia cards can be a pricey combination).
ATI is also produced on a smaller manuf. process (which means that less heat is produced) and they are cheaper while providing more power.
Here are a few laptops that would suit your interests (or at the very least, the kind of gpu's and cpu's they have will give you an idea on what to look for if NewEgg is not an option for you):
http://www.newegg.com/Product/Produ...733&cm_re=Ati_mobility-_-34-115-733-_-Product
http://www.newegg.com/Product/Produ...190&cm_re=Ati_mobility-_-34-152-190-_-Product (this one is much better because the ATI Mobility Radeon 5730 is more powerful than 5650 - and MSI to my recollection has a rather high quality build).
http://www.newegg.com/Product/Produ...093&cm_re=Ati_mobility-_-34-127-093-_-Product (same gpu as the first/Acer one, but I would say that Sony has a slightly better build quality than Acer ... ultimately, it's still inferior to the MSI).
http://www.newegg.com/Product/Produ...092&cm_re=Ati_mobility-_-34-127-092-_-Product (essentially the same as the upper one with a black colour - still inferior to MSI on the gpu end).
http://www.newegg.com/Product/Produ...191&cm_re=Ati_mobility-_-34-152-191-_-Product (this one is $100 over your budget, however, it has a high-end gpu ... meaning that you will not have issues with virtually any game and you can run them in native res with everything pretty much set to 'highest').
That's pretty much it (also keep in mind that any bundled software [bloatware] that comes with a laptop can be easily removed - sans the drivers for hardware devices of course, and that there are free/highly effective/no performance impact replacement programs for antiviruses and whatnot).
Out of those offers (and if you cannot go over your budget of $1000), I would recommend the MSI with the ATI Mobility Radeon 5730. It would be great for games and within your budget ($900).
The following website will give you a BASIC indication on where all mobile gpu's rank (but take this info with a grain of salt because gpu's performance depends on a variety of things and the tests conducted do not use a standard setup - but it's a good basic indication on where cards stand ... however some mid-range solutions on that list of older generations from Nvidia are skewed because of the naming scheme and whatnot).
http://www.notebookcheck.net/Mobile-Graphics-Cards-Benchmark-List.844.0.html
Also ... this website:
www.notebookreview.com is specifically designed to cater to laptop owners and those who want to buy them.
The forums there provide a FAQ sheet with questions that ask in detail just what do you want out of a laptop.
Once you fill it out and post it, wait for some responses and see what people come up with (I try to help out people there, and in the past when I was buying my first laptop, they helped me out as well).
I merely gave you an indication what to look for (and NewEgg is a pretty good site for these things when it comes to price/performance ratio), but you also have to know what you are buying and where (because NewEgg is not accessible to everyone - depending on your location).
Finally, when you found something of interest, post it back here, or on notebookreview forums and ask for other people's opinions (that is if you want to get a good deal on what you buy).