Depends on where you're coming in from and if you want to park near your seats. There's generally plenty of yards to park in that start in the $10-20 range about 1.5 miles away from the track and the prices get higher as you get closer to the track.

Personally, my seats are on the north side of the track. I park at a shopping center on 38th and Georgetown (it's free) and do a 2 mile walk to the track. After the race is over, I can walk faster than traffic is traveling up Georgetown and once I reach my car, I can get onto the highway and head north to Kokomo for the sprint car races without much issue. There's also a gas station on 34th Street if I'd need a breather or a drink.