Just order it through a travel agent or the airline ticket agent. Payment will be the issue, really, more than age. If you have a debit card you could use that, or your parents card if they will let you use theirs. Or you could get a money order and go to a travel agent personally.Most airlines consider someone 17 an adult anyway.Good luck
ALL airlines in the U.S. allow kids 15 and over to fly as adults. Of, course, your parents should approve and know where you are going, but you do not need anything special to fly. Also, kids under 18 do not need I.D. to fly.