Marriott in Napa has a fantastic deal in the winter. $99/night gets you 3 free wine tastings for two, with a free bottle at every winery, a bottle upon check-in at the hotel and a complimentary tasting from a local winery every night from like 5-7. This was from 2010 though so maybe its different. Book through travelzoo.
This post is coming live to you from the Mariott Marquis in San Fran btw. Don't be a complete noodle. Stay here and saunter up to Napa for a couple days, ya nimmie.