I had this problem (still do to an extent). First day of class, I looked back, up at the 200-odd other people in my class, and I didn't know a single one of them! Out of 5 classes, I knew maybe a group of 10-12 people, and that was because we all were part of a program where we are in the same set of classes for a quarter.
I have to say, one of the best ways I found to meet new people was to just talk to the person next to me or whatever, ask them for help, make a comment about the material you're learning, whatever. Just get yourself out there.
Get to know the people you live around. Your floormates, your RA, whatever. Get some neighbors gathered to play a quick game of frisbee or football, whatever. Don't hole up in your room!!
This advice was given to me by friends, family, etc., and it's helped me. I hope it's helped you, even a lil.
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Vote for REAL change.