Need to get to Berlin Hbf by midday to get train.
Berlin Hbf is a station like no other - an engineering marvel with a vast shopping complex sandwiched between the upper deck and the lower platforms.
For a geek like me Berlin will now have two world class gateways - the new airport and the existing station.
Anyway, you just want transport, so here's two points:
1) Berlin Hbf is at the centre of the transport network, and routes from there follow a simple cross - N & S, E&W. However, you may be able to chance somewhere else if your train stops there - check stopping patterns on D-bahn.
2) Naturally, I'd like to say allow time to appreciate the marvel that the station is, but if you want to pass through quickly and have heavy luggage, allow time to get between platforms, especially between top and bottom decks. Lifts can get very crowded at busy times.
And finally, as D-bahn website has been mentioned, that is a great tool for rail travel across most of Europe, not just Germany.
