BCM is one of the better places to get one
http://www.bravocompanyusa.com/
There are several good makers........
I walked in the store looking to buy a AR 15 they were all 950-1100 and 1100+.
I walked over to another counter where they were selling separate uppers and lowers. I got a Spikes Tactical Upper for $525.00 and a CMMG Lower for $250 so for $775.00 I got a very good AR-15 that digests even the steel case ammo without missing a beat. That let me spend more on a good red dot optic.
Unless you just have to have it right now right now. You can buy a good upper or lower separate over a period of time and save some $$$