We can recommend several hotels:

Hotel Bielefelder Hof *, directly opposite to Bielefeld main station - room rates: single room 87,00 € / double room 93,00 € (breakfast included)

ARCADIA Hotel *, Niederwall 31-35, next to "Rathaus" and theatre in the city center - room rates: single room 75,00 € / double room 100,00 € (breakfast included)

Hotel Stadt Bremen *  Bahnhofstr. 32, in the city center - room rates: single room 65,00 € / double room 84,00 € (breakfast included)

Altstadt-Hotel  *  Ritterstr. 15, in the city center  - room rates: single room 70,00 € / double room 90,00 € (breakfast included)

B&B Hotel  * Europa Platz 2, 33613 Bielefeld, direcly behind Bielefeld main station - room rates: single room 49 - 79 € 

Aappartel Boardinghouse Friedrich Verleger-Str. 1, 33602 Bielefeld, in the city center 

Etap Hotel   Detmolder Str. 314, 33605 Bielefeld, 3km to city center, 9km to university 

Jugendgästehaus Bielefeld  Hermann Kleinewächter Str. 1, close to the city center - room rates: guests over 27 years: single room 55,90 € / double room per person 38,00 € / 3-4 bed room per person 33,10 € - guests under 27 years: single room 50,40 € / double room per person 34,90 € / 3-4 bed room per person 30,40 € (breakfast included) - a special identity card for youth hostels is needed, which is available at Bielefeld University 

Guesthouse of "Studentenwerk Bielefeld"   (53.00 Euro without breakfast (+ 10.00 Euro for a second person in the same apartment / common kitchen with another apartment) in Morgenbreede (on the university campus) - 

For more information about accomodation in Bielefeld: http://www.bielefeld.de/de/ti/uebernachten/

respectively http://www.bielefeld.de/de/ti/uebernachten/hotels/

* special university rates, possible only with a special university booking code