There was a Zeppelin in the San Francisco area for a couple of years. Operated by a firm known as Airship Ventures, it was based at Moffatt Field, the West Coast Navy Zeppelin base for the U.S. in the 1930s - and now the home of Google. It cost $500 for a 3-hour flight over San Francisco. I was tempted, but it was just too expensive. I think a lot of people thought that too costly for a three-hour flight. I believe the San Francisco Zeppelin went back to Germany. Sure was fun to see, even though it was much smaller than the Zeppelins of the 1930s.
There's a great little museum at Moffatt Field, worth a stop for all airship fans visiting San Francisco.
I tried to see the airship operations buildings at Lakehurst Naval Air Station in New Jersey back in 2000, but they wouldn't let me in - even though I held a top secret security clearance at the time, that didn't give me permission to do tourist stuff. I happened to fly over Lakehurst a couple years ago, and got a great view of the Zeppelin hangars there.