Santa Barbara is a big county; most of the wineries aren't a 5-minute drive from the beach but more like an hour away. If you have the time I recommend taking the back route up 154 for gorgeous mountain vistas to Santa Ynez and Los Olivos and then drive back to SB via coastal 101. This area is more rustic than Napa/Sonoma, with few chateau-like settings, though as of two years ago that appeared to be changing since Sideways put the area on the map. Sanford was my favorite; I enjoyed driving around the small roads among the vineyards afterwards (yes, I did spit!). If I were to choose a single winery right in Santa Barbara itself I'd check out Jaffurs because I like their wines, but they own no vineyards so it's really just a food processing plant with tasting room. But it's right in town.

Here are a couple of links to wine country:

http://www.santabarbara.com/winecoun...ls/default.asp

gives maps for three self-guided area tours of vineyards

http://www.sbcountywines.com/wine.html

this has listings of vineyards and wineries, and an interactive online map