If you want to talk cheap gaming costumes, then check out MTV's Multiplayer blog. Looks like all you need access to are a mullet-y wig, facial hair and a patriotic necktie of some sort. Plus you need to have attitude in spades and the ability to drop cheesy lines left and right. You can accessorize with bottles of hot sauce, arcade tokens, and a sneer.
Halloween on the cheap. Get a friend to dress up like Steve Wiebe, and you're set.