As a fellow midwestern, and from living only an hour and a half away from you, I have one thing to say.
Son, I am dissapoint. On the up and up though, you're here, which means you'll soon find out what is actually what when it comes to car audio.
Mostly, what you'll find out is that most of the larger companies are money hungry, and thus their products turn into nothing but a pretty picture. On the other hand, there are hundreds of companies with plenty of products, all with different specs and purposes. There will be a sub for you, and you will find it to be pretty cheap. My suggestion to your as far as an amp/sub combo is as follows:
Sundown SA-8 sub. This is an 8" sub with 400W RMS. It's from Sundown, and it's widely regarded as a great 8" sub in terms of musicality and loudness. There are many pluses to starting small like this. First off, the subwoofer is only $135 new, with free shipping from the SSA Store. Second, it takes up very little space. Third, with 400W RMS, you can add another for pretty cheap, and use the same amp I'm going to recommend.
Sundown SAZ-1500D V2 amplifier. Be prepared to wince when you see the price of this. However, don't worry. You'll see that the amplifier works well with your subwoofer, or two if you end up choosing another. You can get the SA-8 as a dual 2 ohm voice coil, and wire it at 4 ohms, or do two and wire at 2 ohms. Either way, it's the recommended RMS rating. If you eventually want to beef up our system, you can get an 800W dual 1 ohm 12" sub, and then get another for a whopping 1500W RMS. Later on, you can get a 1500W dual 2 ohm 15" or 18" sub.
As for a box, I suggest following the recommended specs. I don't know the specifics of box building, but you can look at somewhere between .6 and 1 cubic feet, with a port, tuned anywhere from 30-36 or something, I don't know. I'm sure others will help you more than I can. All I know is with the products I showed you, you can expect great performance and durability. That amp will probably last a long time, and I know those SA-8s are durable.