Please visit the hompage of the German railways (Deutsche Bahn AG, DB) for connections. Search for the train station "MS", which is the abbreviation for "Münster (Westf) Hauptbahnhof" (Münster central station).
Limited parking space is available around the conference venue. Ask for a parking ticket in advance (firstname.lastname@example.org) if you need one. Beware that there is a "Umweltzone" (environmental travel restrictions) in the Münster city center next to the conference venue. Green or yellow stickers are needed (map of "green zone", pdf). Most rental cars will probably not be affected by any limitations.
Train connections from airports:
Münster / Osnabrück (FMO): 0.5 hour (Bus Timetable, PDF)
Dortmund (DTM): 1 hour (Train Timetable, PDF)
Bremen (BRE): 1.5 hours (Train Timetable, PDF)
Düsseldorf (DUS): 1.5 hours (Train Timetable, PDF)
Frankfurt (FRA): 3 hours (Train Timetable, PDF)
Amsterdam (AMS): 3.5 hours (Train Timetable, PDF)