Occasionally, the good folks of the San Francisco Brewers Guild put together a "Meet the Brewers" event. I've never personally been to one, but this sounds promising.
When: Jan 17th, 6-9PM
What: "Toronado will have one beer from each of the Guild breweries on tap."
Where: Toronado | 547 Haight St San Francisco
Guild Members Include: Magnolia, Speakeasy, 21st Amendment and others...
More info can be found on their website, www.sfbrewersguild.org
Remember, Toronado is a cash only venue.