Accommodation Outside CERN
[EN]
There are many hostels in or around Geneva centre, however there are always long waiting lists and you must almost always reserve a room long in advance.
You can find further information through this links:
http://www.fasngo.org/accomodation.html
http://www.cityhostel.ch/site/fr/
http://www.genevahostel.ch/en/
http://www.hostelz.com/hostels/Switzerland/Geneva