Many people too often assume that you can only learn young. Once that childhood is over, it is just too late...
I disagree and firmly stress that you can learn to play whatever age you are. You don't even have to be particularly musical to enjoy learning how to play an instrument. With simple friendly tuition designed to help you at your own pace, you could be well on the way to making some real quality music.
So, if you have been dreaming of playing a piece for years but never thought you could actually do it, think again! Now is the time to pick up that instruments and give it a go. Everybody enjoys listening to music, not that many people ever think they could actually make music themselves though. This can change.
There are a lot of books out there to help too. If you have a piano or a violin, clarinet or any instrument, but don't want a teacher, you could try teaching yourself. Just visit any music shop, and you'll find a whole host of beginner tuition books. I would recommend you flick through a few and the one that you understand clearly and feel comfortable with, is the one you should buy.
For jazz, I would reccommend any of the Jamie Aebersold books. For example:
Aebersold Volume 1, How to Play Jazz and Improvise.
You can work your way through the volumes and they have a very practical approach.
So whatever you choose, whether you would like a tutor or not, you should still consider learning, whatever age you are. If you enjoy music and want to try it out, don't let anything hold you back.
Go for it!