There are so many AR's too choose from and I'm sure Chris can hook you up.
Good thing is Prices came way down!
Which means you'll get more for your money. Maybe with the price savings you can get a nice Vortex or Similar optic
just saw something recently for like $400 with very little if not free shipping.
I would not suggest building your own at first.
Instead I would suggest you buy one already assembled and ready to fire
There are several reasons why I don't suggest building one yourself.
The cost for specialty tools can add up if you don't have any tools it would be better to put the extra $$$$ towards the purchase of a complete rifle.
Mismatched or wrong parts are another reason, it rarely happens but sometimes you can order something by mistake and not be able to use it or return it.
I would say get something of quality and learn the ins and outs of the weapon first then maybe build your own down the road.
I think my next rifle will either be .308 in some form or another.
I am seriously thinking about a Savage Axis II XP for plinking
http://www.cabelas.com/product/SAVAGE-AXIS-II-XP-W-WEAVER-SCOPE-RIFLE/1849999.uts Good luck in your Search
I just thought of this but you can go to some big box stores if you have any down your way and look around and maybe figure out what you like and then see Chris.