First off, congratulations on your win!
Registration is
$5000. If you received any start-up grant money, you might check with the granting organization. Some of them have clauses that will pay for your championship registration if you qualify to attend.
On top of that, you will of course be responsible for travel, lodging, and food. Based on my experience... a charter bus can run $800-$1200 per day, which might be a solution for larger teams. Driving personal vehicles is a reasonable option that makes it easier to distribute costs (people don't usually value wear and tear on their own vehicle as high as they should). You can also of course fly, with per person prices varying from $200-$1000+ depending on where you are coming from. Lodging will run you $75-$150+/room/night (split by # in room), and a fair bet on food would be ~$15-$30/person/day. Most of these numbers can be changed somewhat by being cost conscious, but it might give you a starting point on what to expect to fund raise.