This should help you out, a couple of articles by Dave Barr.
Glutamine - Destroying the Dogma, Part 1:
Glutamine - Destroying the Dogma, Part 2:
I have to add that there are still plenty of people out there that swear by it. Personally, I used to take it, but I can't say I saw a difference.
If you want to spend your money on a safe and useful supplement, go for creatine. However, if you're just starting out, and at your age, I wouldn't bother with anything other than lots of good food, and a protein powder to increase your protein intake. Then, after maybe 6 months of good training, I would include creatine; otherwise, you'll never know whether it's really working for you or not.