Cosmetic dental advice? Is this realistic, or even a good idea?

I am 18 years old. I have very straight teeth and what WOULD be an excellent smile, had I taken care of my teeth when I was was younger. Other than this, I am very comfortable with my looks otherwise, and I would change nothing else about myself except for this. My teeth aren't completely horrible, they are sort of yellow, and I have a lot of fillings in the back. Three of my rear molars are capped in silver, and you can only see them when I open my mouth wide. The worst part is, both of my lateral incisors, (the ones next to the two front ones) have had root canal procedures performed on them, leaving them covered in crowns. They are just regular "matched" color crowns, not metal or anything. So that's my information, here's the thing, I want to be proud of my smile. I can't though because of how it looks. What procedures are there to sort of "make over" my teeth? How expensive are they? I have heard of implants and stuff, but I imagine that they are very expensive. Is it possible for me to have a smile I can be proud of? I'm willing to spend as much money as I can make/earn to do this, even if it's a long term goal. i.e., lots and lots of saving. Someone HELP! Please!
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Going by what info you have given, your age, your history of dental work already done I can say it is an easy fix. Under no circumstance never give in and have your teeth laminated to be all equal in color, spacing, etc. or implants. For your age and given the status of your teeth those options are too radical and expensive. Why mess up your own healthy natural teeth for the sake of a make over? Start your own plan to improve your teeth by using really good products that whiten your teeth. I can tell you factually that getting your teeth whitened at the dentist office is no more effective or get greater results than doing it your self. When you get your teeth to the level of whiteness that works for you, start calling around and getting price checks on replacing your crowns if they are truly that much different in shades of white from the teeth you bleached out. After you choose to replace the the fillings and crowns in front then save up and have the crowns in back replaced. The words crown and caps mean the same thing. So start small and simple steps and lead up to big and expensive steps.
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