By request (from USDMFTW), here is the Mid-Ohio Sports Car Course, near Lexington, Ohio, USA. It is a 2.4 mile (3.86km) road course (including the chicane). The official start is on the back straight after the 180 (according to the information I could find), but I just used the restart/finish line for simplicity.
This is a single lap, but it could easily be made into a flying lap course, if desired. Sectors are already set up for this purpose. (note: it might require tweaking to do so)
Mid Ohio Sports Car Course.zip (1.47 MB)
Here is the track image in game:
And in the Automation Track Editor: