I'm 22 and I don't drink. I find the taste of alcohol completely repulsive. Girls (and guys) who don't drink are not extinct; I know plenty of people my age who don't drink. Maybe we subconsciously gravitate towards each other, I don't know. You probably won't find us in bars or clubs...but as far as finding non-drinking people, that is something that you'll have to take the time to find out.
I agree with Littletad. Even if you meet someone at a library, they could be a drinker at night. School activites, volunteer places, at work...can be places to find someone. Do something you like to do, and there might be someone there of interest. For example, I love snowboarding, and I have met really nice guys on the slopes (that don't drink).
kindergarten? I dunno, I don't know any girls that don't drink... Christian girls maybe? but you won't get laid...;)
look in the mountainous province.. I guess you can find one..:D
There's plenty of girls who don't drink. I would suggest meeting girls at a coffee shop, clubs, and activities at school. There's no real easy way to find a specific non-drinker though. Every girl is different, and the only way you'll learn about their drinking habits is to ask them.
at your age its going to be very hard because even most of the so-called "nice girls" mostly go through a phase in their late teens/early 20s when they do a lot of partying and drinking. most grow out of it by the time theyre 25 though, except occasionally and socially. the best thing I can tell you is to join a group or club of people who share a similar hobby with you. you'll no doubt meet tons of nice girls there and you know they share a passion with you, which is a plus.