If you're in london try the works club in kingston (s london) loads of fit 17-20 yr old slags/students at least 6-7 have ass length hair. One let me play with her hair on the dancefloor - very nice.
There are quite a few clubs like that - I have no problem seeing great long hair often when I go there.
Guess after they are 17-18 girls begin to keep shortening their hair. Catch em young eh?
Riderx