Advice for international students
The employment market situation and the rules to get a work permit do not allow students to finance their studies by work only. Work permits are only given for part-time work during the semester (120 working days or 240 part-time working days / from August 1, 2012). All other work needs an additional permission from the employment office. Students from the European Union do not need a work permit. More information are given here (German / PDF).
But the current situation on the German employment market and the course load restrict the job possibilities.
In addition to the mentioned possibilities to finance your studies, the following links are recommended: