You find the best overview on public transport system at You can also find timetable information including prices at (yet only in German).

Here is the transport plan for Kreis Soest:

Here is the transport plan for regional trains in entire NRW (North Rine-Westphalia):

Verkehrsplan NRW_2015

Since a bus ticket from Rüthen to Lippstadt currently costs 6,90€, here are some advice for paying less:

It is often possible to get a better price with the so-called 4er-Ticket (one ticket with 4 journeys), Tagesticket (a ticket for the entire day), 9-Uhr-Ticket (from 9am till midnight) or with the Schöner-Tag-Ticket NRW (a ticket for the entire day in entire NRW):

Fees for Public Transport