Hmm. Well, I'm a virgin and 16 right now, so I'm younger than most of you, and I have a somewhat strong desire (especially for a female) to have sex. I've had it since I was 15, it's grown stronger recently, as a few of my friends which are both male and female have been either having sex or close to it at least (oral sex, etc).
I've been offered and hinted at to be given sex by two guys earlier in the year, but I've ignored them. Although I may have a strong desire, I'd rather have sex with a male best-friend or a boyfriend, because I don't just want the "feel good" factor, I want the emotion, commitment (if boyfriend) and/or fun in it aswell.
But I think at the "moment of truth" I would (or will if I'm being optimistic) be shy and feel very pertrified, because I absolutely despise my own body and looks.