Päivää!

I didn't read all the responses, but you can also take private shuttle buses both in an out of SFO besides BART to most of the major outlying towns and cities.

Buses pick up passengers at SFO on the lower level (outside the baggage claim area) on the center island at the blue pillars. International Terminal pickup is located at the Arrivals Level, outside customs in the outer roadway center island at the "Airporters" zone. The bus will stop, the driver will call out the destination, and you can then go on whichever you wish.

For instance, if you wanted to start your tour where I live up in wine country, you could wait for the scheduled Airport Express bus service particular to my area (www.airportexpress.com), which runs to and from different towns from the Sonoma Airport all the way down. I take these buses with my folding bicycle when I want to take an international tour.

There are a number of express bus services like this, but I don't know all the names. I'm sure you could google it if this sounds like a possibility you would be interested in.

Have a great tour!