Sacramento is the most convenient, but less flights so cost may be an issue. Oakland has a few more flights and is also about an hour away. San Francisco is about 80-90 minutes away but lots more flights so might be cheaper.
Wineries are everywhere. Are you looking for a nice tour, impressive winery or fantastic(read expensive) wine? What kind of wine do you like?
Hotels, in season are crazy expensive. Look for some deals on the net. Lots of B&B's if that is your pleasure.
Smoking is limited due to strict Cali laws. Bring smokes as there are only a couple of shops and high taxes.
