Unless you ABSOLUTELY need the cash, don't worry too much about getting a job at that age. If anything, consider a part-time job or maybe a summer job so you have some experience without cutting into your life and/or school. I've had a summer job since I was 14-ish and, while it's nice having some extra money, I kinda wish I had spent the time on what I wanted to do instead of being swamped now.
One thing to think about is what you want to be and possibly start working towards that. This doesn't apply to all, but for me to get a job, I should have a portfolio of work so employers have an idea of what I'm capable of. Could I get a job without it? Sure, but having it never hurts. My one friend wanted to do children education so she started out babysitting and then got a job at a daycare while she got her degree. If you know in advance that you need to do something to increase your chances of getting a job, I'd suggest spending your time now on it instead of worrying about experience.
My one professor said that a few of his students applied for positions that said they wanted people with 6 years of experiences and his students got the jobs straight out of college. So don't take those "years of experience" requirements too seriously. If you have all the other skills but don't meet the experience requirement, it doesn't hurt to apply.
If you are serious about wanting a job, then consider going to any place you'd be interested in working and simply asking a manager if they have any job openings (or if they will be hiring in the near future). Also, if you're applying, try to be professional. I once had a girl who was applying for a job, come in wearing a mini skirt and a bikini top. If you are going to McDonalds or other local stores, you don't need to break out a business suit or anything, but at least have a nice top and pants or skirt. Kinda business casual I guess.
Also, try not to get discouraged by not getting a job or hearing about someone else's experience. I have this issue, so I know this isn't an easy thing to do, but you're better off applying and having nothing happen then not apply cause you don't think you'll get it. Sooner of later something good will happen cause you're trying.