Hi,
This is my first post.  I have been seduced by the idea to build my own AR15.  I know very little about the AR15, I have just started learning.  This will be my first long arm.  I want this first rifle to be M4 A3 post-ban carbine.  I want recommendations on what parts to build it with, brands, styles etc.  I assume there is a post somewhere comparing the different brands and styles of different uppers and lowers etc.  If there is, I would appreciate a link.  Just from browsing I have found so many brands that I have never heard of.  I want to definitely stay under $800 (preferably around $600) to start with the possibility to upgrade in the future.  I would like eventually to have a red dot sight and a mounted scope.  I am not opposed to buying used.  I would also like to be able to attach a side mounted light probably surefire.  This project is for fun and experience.  Not a weapon I will use for home or other protection, although my requirements for accuracy and quality dictate that it could be.  I'm in Columbus, Ohio.  

Okay, my recommendation is that you start with
one of the DPMS, chromelined 1/7, barrels (16" or 14.5") from [url=ar15.com/forums/topic.html?b=7&f=22&t=156897]CMMG[/url] on the EE!, Jeff or John at CMMG can even set you up with a complete upper assembly, and any of the other parts for your build.
I would also recommend the Cavalry Arms stocks and furniture, available from [url=ar15.com/forums/topic.html?b=7&f=22&t=165879]Adrenaline_Arms[/url], also on the EE!