two of my roommates are all about the hair extensions. the blond one has a jessica simpson set and another synthetic set that i believe she paid about $100 or so for. then she found some sort of hair warehouse walking down the street one day that sells all this human hair in every possible color. she got a whole bunch for like $30 or something.
the brunette one also had the same type of synthetic extensions and then got some of the real ones as well that were just a *perfect* match for her hair. anyway, she loves them and seriously wears them all the time. they both love them actually.