Check about a month before you travel - there might be BART service to SFO by then. It isn't open yet, but it could open later this summer. That might be the fastest and cheapest way into the city.

I'll let the experts recommend other bus/train connections if you are trying to go super-cheap and there is no BART at SFO. Whenever I've gone to SFO, I have been with other people, so we've just jumped in a cab.

Hotels: I stay at the Grand Hyatt downtown every time I go to the city. I think it's a great place, and I always find it for ridiculously cheap rates. Ordinarily I'm a Marriott/Hilton guy, but when there are $109 Expedia Special Rates for the Grand Hyatt and MR/HH want double that for a points-earning rate, I can't turn it down. Great hotel, big rooms with balconies, excellent service. It isn't near Fisherman's Wharf, but it's less than a $10 cab ride away.

Whatever you do, don't forget to stop and say hello to the sea lions at Pier 39. You could easily spend the entire day sitting there watching them. Or maybe that's just me!