I am a USC student. I live in a my fraternity, so I bring my advice with the utmost objectivity...
Some nice places in the area are:
The Medici (nice area, downtown, management is hard to contact)
The Orsini (nice area, downtown, management is hard to contact)
The Met (hear it is nice, downtown)
Loft living is booming in LA. Loft living is awesome. Check out the Pacific Electric lofts. My friend lives there, and it is gorgeous. There are a lot of other places that are being renovated, so check'em out.
There is a new building being built by Conquest housing on the corner of Exposition and Figueroa (google Conquest Housing and you'll find it). It is really close to campus. Next year is the first year it will be open.
Basically, you do not want to live South or West of campus. Living North is nice, and there is not much housing to the East.
All these people that want to live in Pasadena, Marina Del Rey, Westwood... you are crazy. Do you have any clue what LA traffic is like. As an undergrad at USC, if you can't bike to class, you live too far. As a grad student, if you have to get on a freeway to get to class, you are living too far. Get real guys, you do not want to drive an hour or more each way for school.
I wish you all the best of luck finding housing. PM me if you have questions.