To the person who found this site by Googling "Is it too late to start classical guitar at 17?":
No it's not!
Yes it's easier to learn things when you're so young that everything you do is a learning experience, but that's not the whole story. Passion, enthusiasm and focus are easier at an older age. At 17 I suspect that passion, obsession even, is something you understand completely. Where a child might work at something because it captures their quicksilver interest for while or because Mom told them to, teenagers will focus to point of exclusion of everything else. And that's what it takes to become an expert.
Another thing to consider: while tiny guitars exist for very young students most people can't really learn to play until they've settled into the body they're going to have the rest of their life. At 17 you could still have a growing to do but you're closer to your final size than a 10 year old is.
If you read the bios of the Yngvie Malmsteens, Eddie Van Halens and Steve Vais of this world, (you know: guitar heroes) you'll find that most of them spent the better part of their teen years sitting in a bedroom practicing. There's no reason that this wouldn't work for classical too.
I think it's a shame that the Classical world focuses on prodigies so much. It creates an unrealistic impression of who can and can't play classical music. Just because you weren't playing Bach Suites at 3 months old doesn't mean you don't have something to offer. If more people who grew up outside of the Classical music world would take up playing it, then maybe we'd have more interesting interpretations of the repertoire. I'd love to hear someone who hung with Dad on the construction site as a wee tyke play Stravinski, or someone who's childhood passion was ice skating play Debussy.
Yet another thing to consider: Classical musicians can have careers that last until they die. The ageism that is so prevalent in pop and rock music simply doesn't exist. So why is there this emphasis on young prodigies? Craziness I say.
There we go, my 2¢ worth. [steps off soap box]