there is a big half pipe at the indoor park in Berlin. It's the home ramp of one of the best european half pipe skaters, Jürgen Horrwarth.
On Sk8Mag.de, I also have nice map of skatespot, on shows some spots in Germany. Some very crazy spot is [http://www.sk8mag.de/Spots/Berlin_Marienfelde/]Marienfelde[/url], I've never seen anything like this.
In my opion, the most interesting place for you would be the indoor spot, Skatehalle Berlin.