Is it legal to sell a lower receiver, in your state, without an FFL. I'm not saying a dealer sell it, just the guy next door type of deal. Is that considered a private sale? The reason I ask, if I post in the EE section, that I'm looking for a lower, and someone from my state has one, do we still have to go through an FFL?

If you are trying to circumvent a NICS check because you are not eligible to own a firearm then you would be committing a crime.  

Most states allow private sales as you describe in your post.  This is the so-called 'Gun Show Loophole".  Some allow only long guns but not pistols/revolvers which still have to get transfered through an FFL (ie. RI).  Some require only FFL transfers for all firearms.  You have to check KY state law on this and should post this in the KY forum if you haven't done so already.  They will be able to tell you right away.  I would be surprised if it wasn't legal to do so.  

Quoted: If you are trying to circumvent a NICS check because you are not eligible to own a firearm then you would be committing a crime.

I am eligible to own a firearm seeing as how I'm 23. I've passed both background checks on the only two guns I've had to do paperwork on. The less my name shows up in our governments computers the better IMHO.