I can second the bockbierbude option! Once you register and install their proprietary app (is a sort of P2P torrent sort of app), get an individual "download ticket" from their website this is one of the best ways I've found to stay current on new cars, tracks and mods.
LOVE the DRM update! The sounds are fabulous and the cars are a blast to drive. I've been trying to tame the monster that is the M1 at Laguna Seca... wow! What a handful! Wish there was a variable boost setting.
Anyone have any good setups?