I ABSOLUTELY recommend the Wine Country Tour out of San Francisco!!!
The tour starts at the Ferry Building in San Fran. You take a small tour bus over the Golden Gate, visit FOUR wineries (when I went, we visited V. Sattui, Domain Chandon, Luna, and Andretti), you get a picnic lunch, and you have some choice in the tastings you do.
The tour guide shares a lot of information about the region, the history, and the wine history... which I actually really enjoyed.
To return to the Ferry Building in San Fran, you take a ferry ride, which goes by Alcatraz and the Golden Gate.
My husband, who only went for my sake, really enjoyed this tour too.
It costs $90 per person, plus tasting fees at a few of the wineries, but it was worth every single penny.
The website for the tour is: winecountrytourshuttle.com
Was on the tour about a month ago..... LOVED IT!