Any of the longer tracks work well, Aston Historic, Kyoto GP, Westhill Rev etc etc.
This conversation comes up alot, and the conclusion is always the same, it seems people WANT to drive the LRF class, however, theres not enough of those people around to get good racing going.
CTRA ran an LRF server, but closed it due to lack of use, I think it boils down to people wanting "easy" racing.