yep, i had a receding hair line and thinning vertex starting at 16/17. by 18 it was becoming more noticeable by the day. For a while I grew the hair out to hide it, but i usually ended up wearing a hat 99% of the time anyways. finally, at 20 i cut the hair down short (maybe an inch and a half) and it looks much better. the more bald i go the shorter it will get.
i've been on propecia a little over two years now and it seems to have at least helped maintain my hair count on top of my head. maybe it's cause i'm young or because i've only been on the meds for 2 years, but i definitely haven't noticed any loss in libido or anything.
so, to all you younger guys losing it, you're not alone. and if you're older than me and losing your hair - i know it still sucks but i would have given anything to have my hair until then.
peace
-B