deadbart :
that looks good but i heard the theres not much point in getting a 7870 over the 7850 :/
i really put the 7870 because it did fit in the budget. as far as getting a better bang for your buck, i'd suggest looking at benchmarks of games you are going to play. (though it sounds like you have)
personally myself, i like the GTX 570 because nVidia
seems to perform better in some of the more popular games; but that is strictly my opinion.
i hope the suggested build will give you a fundamental idea; because that is what i thought you asked for more than a "finished" build.