If you can find it, the Asus N81VP would be a decent choice (around 800 USD).
I certainly don't want to steer you away from the other laptops. The 5470 in them will be ok for gaming, just don't expect miracles. If you want to look at how it performs, take a look here: http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5470.23698.0.html
It should be ok for games at medium to low settings on lower resolutions.