Interview students on campus who are natives of the city. If you're writing about the stress of job searching, ask them how they feel about the job market regionally and why they feel that way. Also mention a few success stories from students who landed good jobs and ask how they got the jobs.
Interview local faculty members of various academic departments. For example, if your story is about the dangers of childhood obesity, you may want to talk with a medical school faculty member about what the childhood obesity statistics are for the city he or she lives in, and what is being done locally to combat this.
Attend local events that pertain to your story. Suppose your campus news editor assigns you a story about the latest fashion trends. If a few local boutique owners will be hosting a fashion show concerning these trends, it would be a good idea to go. Also interview the boutique owners and ask about the trends.
Read the local newspaper daily. This helps you keep up with everything that's going on in the city. Also pay special attention to the stories that relate to the section of the campus newspaper you're assigned to. If you're in charge of writing about crime issues, you would read the city's metro section.
Listen to local radio and watch the local news. Listening to talk radio programs gives you an idea of what city residents think about certain issues; it may also generate new article ideas.