Never been there but know where it is.
In Livermore, (much closer to Dante and me) is Wente Winery. It is not a permanent setup like Mountain Winery, but they set up tables and you have a meal and a concert.
Coming up they have Heart, B-52s,Frankie Valli, Blondie/Pat Benetar, Steve Miller Band, Diana Krall and the next week her husband Elvis Costello, and James Taylor. Plus there's a golf course there.