Most of the friends I have in college came from a message board for the school (including my boyfriend
). You could look and see if your school has one. Ours isn't run by the university, but there might be some that are.
Facebook is a good way to get names and faces of people in your classes, then you can strike up a conversation the next day. Or you could start a study group for a class you really dig, maybe one that's optional, so you get people who share your interests.