Jim's Links Page
quattroforum What it says on the tin - UK based quattro forum by the users, for the users.
Audi Fans.com - subscribe to the mail list.
AudiWorld Forums Great Audi forums - very useful.
Audi quattro parts
quattro owners clubUK Ur quattro owners club with info and forum
Martin Pajak's quattro pages Canadian enthusiast site
SJM Auto-Technik Good info here - especially on the injection system.