Check out http://www.laidbackracing.com
for lists of Bristol campgrounds and "pop odoms" which are fields where their owners open them during race weeks. Also from http://www.bristolmotorspeedway.com
web site you will find lists of campgrounds near the track. In the Bristol Motor Speedway news letter I received yesterday they listed 4 new campgrounds associated with the speedway. Call Angela at 423-989-6944 or email her, email@example.com
I don't think any campground directory will list as many places to camp as the above websites. Most are dry camping, there are some with water, some with water & electric, and some full hook up. They are all expensive, ranging from about $100 up to over $500.00.
So check these websites and call if numbers are listed for availability and prices.
I have been camping there since the mid 80's, so remember you are race camping. Like most places near race tracks you will be awning to awning, with generators running 24 hours a day, and parties that run as long as the generators.