It can be VERY daunting-there are many, many, many variations out there and even opting for-say- a GTX650 will show close to a dozen options.
I'm sure others will have different opinions but I'd grab a HD6850 while they're still around. Cheaper than the 650Ti it has very similar performance and is far ahead of the only slightly less expensive non Ti GTX650.
Here's some Newegg prepared earlier:http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007709%20600083901%20600083830&IsNodeId=1&name=Radeon%20HD%206850
And a nice little review and chart for F1:http://www.techpowerup.com/reviews/ASUS/GeForce_GTX_650_Ti_Direct_Cu_II/14.html
In the above review, they use a much more powerful CPU/RAM configuration but also max out the game settings. While you will NOT see those framerates at those settings, the cards will fall into the same hierachy.