This is one of those questions that could have been answered by using the search function here.
Anyways, for $200, you should consider a 6600GT. They are good performing cards, and have good value. They are available in either AGP or PCI-E flavors, depending on what you computer requires.
Have a look on www.newegg.com
Most people recommend eVGA cards. I personally like Gigabyte. They perform just the same, but have excellent value (locally anyways, I dont know about newegg).