well, since I'm not much of a fan of gaming headsets (most of them are crap anyway), this is something I'd go after>
sound cards (because without a decent sound card buying any headphones above $30 is wasting your money)>
Sound Blaster Z - games above everything!
Asus Xonar DX - fun all around
Asus Xonar ST/X - if you're lucky to find a refurbished one for a great price...
headphones (better sound quality compared to a gaming headset and you can plug them into your mp3 player/ipod/cell phone to listen to your music and not look like a complete retard)>
Alienware Ozma 5 - aka rebranded ultrasone hfi550 for the cheap...
Shure SRH750DJ - for the bass, but can be a bit uncomfortable...
Sony XB - for the extra bass...
and a clipon mike like the Zalman ZM-MIC for about $10 (because it's useless to spend more imho)...