E38, CGTI and Classic Audi are my usual haunts, but I'm also a member of Lancer Register, ClioSport, RetroRides, 106owners, Pistonheads, Mondeo Enthusiasts Group, Passionford, Renault Turbo OC, Driftworks, Morris Minor OC, Audi Sport, Talk Audio, S2 Forum and a few others I've no doubt forgotten.
The places you end up looking for business eh