You can book your ticket to Munich Central station (Münchchen Hbf) through Deutsche Bahn's online booking portal:
Deutsche Bahn Timetable & Booking
The conference location
Kolpinghaus München
Adolf-Kolping-Straße 1
80336 München
is about a 10 minute walk from Munich Central station.
You can also use public transport (MVV) to get there - use München Hauptbahnhof as Start and Karlsplatz (Stachus) as Ziel.