If you're spending more than a couple of days in Napa you owe it to yourself to spend a day in Sonoma. There's a certain charm to Sonoma, a laid back agricultural feel to this town that makes it a nice contrast to the more sophisticated Napa. Taste in barns, picnic just about anywhere, cheap tastings, it's a throwback to when wine tasting wasn't an expensive event but something you did on a weekend whim. And yes, you can still find FREE wine in Sonoma and special discounts.
So check it out: Local Wally's Guide to Sonoma at SonomaTouristGuide.com and let me know what you think. And yes, I'll build you a custom stop by stop agenda for free if you get a Wine Pass and need help picking them out.