It's not a matter of money...... but is expensive.
The bigger issue is permits. There have been a few people that have tried to build a track but eventually gave up after not being able to get permits.
Do a search on Liberty Motorsports to get an idea of some of the issues.
And here is some info on the track over in NJ
http://www.nj.com/cumberland/index.s...otorspo_2.html
As you'll see 15 million isn't gonna get it done.