First things first.
1) check out your local and state laws about gun ownership and registration.
2) buy a stripped lower from you local gunstore.
3) visit palmetto state armory and get a rifle kit, make sure it has all the thing you need to be legal in your locale.
4) make sure you have a rear sight, some extra mags, lotsa ammo, a cleaning kit/supplies.
5) build it.
6) take lots of picture after your build and as your shooting it. We needs our pron.
7) shoot it.
8) shoot it n lube it.
9) shoot it.
10) consider modifications at this time.....and buy some more ammo.
If you can wait a bit, I'm working on a little document with very basic information for the first time buyer, should be done in a couple days. Kep ur eyes peeled.