NASCAR company headquarters are in Daytona Beach, FL, which also happens to be where the first race of the season, the Daytona 500, is held annually in February.
The address is 1 Daytona Blvd., Daytona Beach, FL.
Approximately 1,000 employees work for NASCAR. You can contact the office through NASCAR's customer service number at 1-800-630-0535.