You'll know you're getting close to the track when you starts seeing signs on the side of the road saying "Race Tickets Here". They're everywhere every time I go to Bristol, expect to pay high prices for scalped tickets at the night race.
I've no experience buying scalped tickets, but I've heard that if you are willing to wait until the race has begun, you can get tickets at a much lower price. Not a bad idea when they are selling the tickets at the track, but if you have to wait a couple of miles from the track, it might even be less. If you give this a try, give a good account of what you witness.
I got some scalped tickets at a nascar truck race at nashville. We ended up with every good seats, It was in the Toyota section. Could of went to the hospility tent, but never made it over there. Paid like 10 or 20 bucks for each ticket.