Finding short-term housing in a new city can be challenging. It may take resourcefulness and perseverance to find a place to live. The first step in your housing search is to make a list of all the people you know who have connections in the city where you'd like to live. Include long-lost relatives, friends of friends, even parents of your Oberlin friends who are from that city. Contact everyone on your list to see if they can put you up for awhile, or if they have ideas about where you could look for housing.
In addition to contacting everyone on your housing list, you may wish to use some online sources to widen your search. Check the temporary housing links on the internship section of the Career Services webpage. You may also wish to look into housing options at universities in the city where you will be living. Some universities rent out dorm rooms on a temporary basis, and some have housing offices that list sublet advertisements. You should also check the Oberlin online classifieds to see if any alumni have posted sublets in the city where you'll be.
Occasionally, Oberlin alumni will be willing to provide temporary housing for students. You can search for alumni who are willing to house students in the Obieweb database. Meet with a career advisor for more instructions about how to do this. The number of alumni who have housing available is typically quite low, so don't plan on this option as your only strategy.
Another challenge students sometimes face is that many internships are unpaid. Don't let your need to earn money over the summer deter you from looking at unpaid internships. If you find a great unpaid internship that you'd love to do, apply for it. Remember that many unpaid internships are flexible enough to allow for part-time work elsewhere. You may be able to work a couple of days per week at the internship site, and alternate with a few days per week at a paying job. This will make for a busy summer, but the experience you gain may well be worth the extra effort.