Havent been there but there is a place above the symphony that is a privaate members club... you would have to know someone, but if you can find a member that place is supposed to be that best for networking. Have you also tried to look in LinkedIn for any events?
You know last time we were there we checked out this really random German place not far from the wharf and it was really good, especially if you like beer. Here is the yelp link - http://www.yelp.com/biz/leopolds-san-francisco-2