well i have my own bluetooth headset for my phone but i used the jabra blue tooth headset that came with Warhawk when it was released last august, i remember buying the game and the headset for $40, really good deal...
if you can still find the Socom usb headsets for like under $20, then get one, i heard their pretty good...
otherwise, ask Skinnypup, he seems to know pretty much anything and i do mean anything about the internet... dont try to contradict him though, because Skinnypup is right and the whole world is wrong...