ShortyRock,
I suggest that you go to our main site,
www.ArchWired.com, and you will find the answers to all of your questions.
But anyway basically here are your answers:
$5,000 is the average for a full 2-year treatment and usually includes the retainers at the end.
Yes, ceramics are more expensive than metal.
The ligatures (little rubber bands) that hold the ceramic (or metal) brackets in place stain, NOT the brackets themselves. The ceramic brackets do not usually break but can be harder to remove at the end of treatment.
A retainer might be able to fix your gap, but you'll probably be happier with the long-term results if you got the full braces treatment instead. I'm sure you don't want to go through this again as an adult, do you?
Invisalign tends to be more expensive than regular braces. Have you considered lingual braces (behind the teeth)?
As far as getting "only the top done" that is up to your orthodontist. Most people think that braces are only about how your teeth look, but they are also about how your bite functions. If your top and bottom teeth don't meet properly you will be in for much bigger problems. So if your ortho is recommending both top and bottom, you must listen to him because he's telling you this to ensure that your bite doesn't get messed up (the way your top and bottom teeth meet).
As far as dental insurance, you can check out DentalPlans.com (there's a link on the main ArchWired page) or some other similar dental plan sites on the web. These aren't actual insurance plans, but discount plans set up with orthos around the country. I agree that perhaps a local dental school might be able to help you as well, so check into that.
As far as "wanting them off as fast as possible," I'm asking you to please remember that things take time. There ARE guys your age with braces and believe me, girls won't avoid you because of it. My own daughter probably won't get her braces until she's about your age because her adult teeth are coming in really slowly. You're not alone. Don't rush your treatment. In the long run you'll be happier with the results if you do what your orthodontist recommends.
FYI, the money isn't paid for all at once. Your parents would put down about $1,500 at first, then pay the rest in monthly installments. These costs might not cover the x-rays, however. But, the x-rays might be covered under your parents'
medical insurance.
Please encourage your parents to visit ArchWired.com to get the lowdown on the whole braces thing. And feel free to ask any questions you want here on the forum.
Best of luck to you!
I'm the owner/admin of this site. Had ceramic uppers, metal lowers ~3 years in my early 40's. Now in Hawley retainers at night!
Its great that you are researching so much and really taking an interest- it shows that you are very mature. 
