I have a crappy one built into my laptop, only runs at 30fps so the track isnt as smooth as it could be. Apparently the best one to use is the Playstation Eye as it runs atr 100fps. I am tempted to try and find one on ebay and try it.
The free track software can track the TIR head clip, borrowing a headclip off a friend this week so I can try it and if that works better I am going to buy the head clip and stick with that.