I'm with Red on this one. Not all amps are created equal.

If it's fidelity you're after, it's expensive. If you can hang with that, then there are a few components that could easily be suggested. I'm personally biased towards Diamond Audio stuff because it's the best stuff I've personally used. I know there are a handfull of others that also have very very strong reps of being on top of the food chain as far as fidelity goes.

First you should establish a budget. Second, you should establish a priority list (do you want to give up room, are you willing to make upgrades to your electrical system, do you want super clean install, etc.). And finally, you should understand that there will ALWAYS be a trade-off when you do this.

Fidelity is much more difficult to obtain than raw SPL. You get a big box, big power, and you have high spl. High SPL is not the same as high fidelity. For high fidelity you will need clean amps, clean components, and clean install. All that adds up to $ any way you slice it. Assuming by your statements, self install is going to be out of the question. If so, then you will have to factor in for probably the most expensive part of the project; Labor. If you get fancy, custom work is even more expensive.

Moral of the story is that the rule of thumb is usually going to be; the more high fidelity you want, the more it's gonna cost. SpL is cheaper to get (for the street) but is not fidelity. For what it sounds you want, you'll probably need atleast a good HU, clean 4 ch amp, 1 sub, 1 set of components. What brand those things are is totally dependent on your budget. It could be $1000 or it could be $5000.