Originally Posted by poikilotrm
That being said, there are a number of good makers out there. Armalite, Bushmaster, Colt, CMT, Stag, DPMS, Windham, and a ton of others can provide a good lower.
Original poster, I would agree with waiting a few months for prices to come down if you can. If you want a basic complete rifle your best option is a Colt 6920 or a Smith&Wesson M&P15.
There is a wealth of knowledge online about Ar15s, modifying and upgrading them. Take your time and do your research.