You can check here for vessel arrival times.

http://www.sdmis.org/schedule/

There is also a web cam where you watch them unload your car. Porsches typically hitch a ride with VWs and Audis on VW Transport boats. Your dealer should be able to tell you which ship your car is on. And if you are as crazy as I was, you can even watch it go through the Panama Canal.

I was lucky, the ship that my car was on was the Utopia Ace. When it picked up my car in Germany, it made the local news because the ship was brand new and the largest in the world. So I was able to see it leave Germany, saw it go through the canal, and then arrive in San Diego.