I agree with @alain94040. The best co-founder are your former classmates, co-workers, and the other people you have already worked with and know. Look for really smart people who are around you that possesses a skill that you lack. i.e. If you're technical, try to find somebody who is business oriented.
I would also hit up Meetups, Users Groups, and maybe Alumni mixers. Chances are you might run into an old co-worker/class mate that shares similar interests.
I would also hit up Meetups, Users Groups, and maybe Alumni mixers. Chances are you might run into an old co-worker/class mate that shares similar interests.