Just make sure you register when it opens in early March. Only 100 spots and they go fast.
Have a track bike, you're going to be riding with 99 other people who have track bikes. Be aware this means: high bottom brackets, short wheel bases, aggressive geometry, no brakes and probably shorter cranks. Figure out what gearing you will be comfortable using, the recommend gearing is generally 49x15, three time winner Dan Chabanov used 48x14.
Research the course, there are anywhere from 5-8 turns in the very technical circuit. Understand how to ride this type of race brakeless, I recommend practicing in a neighborhood that has a similar layout.
Be comfortable riding in a pack, try to find some other fixed riders to ride with since the speed moderation by a brakeless peloton is very different than a road peloton. Learn as much as you can about how to (what is essentially) road race a fixed gear. It's a lot different than a geared bike and there's a real lack of information out there. This thread has some good tips:
http://www.bikeforums.net/showthread...olding-me-back
The race is unsanctioned and open to pretty much everyone, but be aware that when you get lapped, you're pulled from the race. This can happen pretty quickly. The previous winners were/are now, pro cross racers, pro roadies and very strong track racers.