Getting to Potsdam:
Potsdam is a relatively small town located in the southwestern part of the Berlin/Brandenburg Metropolitan Region. Potsdam does not have its own airport but Berlin is serviced by two airports: Tegel (TXL) and Schönefeld (SXF). For more information visit Berlin Airport.
As an alternative to flying, the main train station in Berlin (Berlin Hbf) has connections with several major cities in both Germany and Central/Eastern Europe. For timetables see Deutsche Bahn.
Once you reach Berlin there are various public transportation options to reach Potsdam. Buses, subway, and train lines connect both airports and Berlin Hbf to various locations in Berlin and Potsdam.
For finding a suitable mode of transport and their timings, please visit BVG or VBB. Smartphone users can access the route planner through Mobil BVG.
The taxi website for Berlin and the surrounding area is Taxiverband Berlin. Although it doesn't have an English-language version, you may still want to check the fare calculator. The official fare is €3.20 plus €1.65/km for the first 7 km and €1.28/km afterwards.