It is always reassuring to me, when I come to a Bahnhof for the first time, to have an idea of where I am going. A few years ago, I ordered the train schedule CD from the Bahn. Included were the station layouts of over 100 stations around Gemany. Here are a few major ones that might be of interest.
Mainz Hauptbahnhof
Note: Tracks 11 (used for regional trains to Koblenz) and 13 do not go through the station, but are stub tracks coming in from the NW end, next to Track 1.