Not really anything you can do here. You could have purchased a laptop with an ATI 9600 that would have played most anything, but you would have been looking at roughly double the price of the one you have now...
Also note that ATI is working on a system that would allow for video upgrades in laptops. ATI has once again paid attention to the needs of the user and stepping up to the plate.
Also keep in mind that companies will be slow to adopt anything that might slow down laptop sales. And the lack of upgradeable drives alot of new laptop purchases. So you will have to shop around and probably pay a premium to get one of these upgradeable units.
If cash really isn't a big deal to you then head over to
http://www.voodoopc.com/ They have extremely nice "gaming laptops"