Well, it is very good that you are thinking about this early and if you stick to it and stay focused, you'll certainly be where you want to be at a young age.

A brief little about me, I was in your position and graduated in '08. I had the same contemplations you did between military and civilian route. At that time, the market hadn't quite crashed and money wasn't necessarily my problem. My end goal has always been to fly for a passenger airline, granted I would do any other flying (such as cargo or corporate) if the career possibility was there. Although most people told me to enlist, and the sales pitch is good; get paid, no debt, all kinds of flight time, and airlines love military pilots. I don't know how true any of that is, but that was the year that the percent of air force pilots flipped and more pilots were flying drones than actual airplanes. That thought scared me. I didn't want to sign away 10 years of my life or so for a chance to get in the aviation program, and if I got in it would more than likely get met with "your new airplane is a UAV." I just didn't want to spend 10 years of my life and end it with 0 flight hours.

So I enrolled in college, UVU online to be specific. I actually just graduated spring of '12 with a bachelor of science in aviation. I liked the program and think the degree is wonderful to have. The price tag is not so wonderful; with no scholarships or grants, I spent about $70,000 or so. I don't think that's too bad considering a degree and all my pilot certs in four years. I also just got hired at Great Lakes Airlines after being a flight instructor for a year. I am very pleased with the route I took, and would encourage anyone looking to an airline career to do the same. The military is shrinking their budget every year and I believe they are fast becoming the way of the past in order to become a pilot. But that is just my opinion.

Some other options you have; if $70 - $80 grand of debt isn't your price range, and you'd rather not do the military route, consider ATP flight school. They do fast track to airline pilot programs and they'll cost somewhere around $55,000. They'll go very fast, which is something I don't necessarily like, so make sure you go above and beyond to learn what they teach you and appreciate your time there as a flight instructor. The program is good and they can make you an airline pilot FAST, but the drawback is you don't have a degree. It is also possible to do college online and get your certs with ATP, but would probably cost about $15,000 more than I spent with a more local flight school.

All in all, good job on getting off to an early start. Aviation is something you must stick to, and be very motivated, in order to succeed. If you have any more questions, please feel free to ask. Hopefully you'll take all options and think about what is best for you and the life you want.