I'll make the same suggestion I do to lots of these threads: Vintner's collective in Napa. Its open later than most tasting rooms, and represents quite a few different wineries (about 10 I believe).
Other places: Jarvis is the single most impressive tasting experience -- someone here described it as Disney meets napa. Guilliams is great, and just down the hill from Pride & Paloma. Bressler is great as well

Many many threads on this topic. Make sure to hit Taylors Refresher!