TexasCHLforum.com

I shopped and shopped for all the pieces for mine, and still came out pretty close to $600. For that money I could have just ordered a complete kit (less lower) and then bought the lower, and had a better end-product for less money.
But I like finding deals and I like the building process.

Have fun at the gun show

Rex

For the full progression, you need to include the "hacking a lower from a hunk of aluminum with chisels and files".

And then there's the "Take a chunk of bauxite and heat..."

I've been following AR15.com for some time, as I'm assembling ARs also - just finished the first one. From what I've seen, any of the lowers will do just fine. Right now the lowest priced lower is from EssentialArms.com.
They cost $77 plus shipping.

Another alternative is an 80% finished lower.
All the difficult machining is done, you just have to (accurately) drill and ream a few holes, possible clean up the magwell. A little less than the EA if you shop, with the bonus of no FFL or 4473 involved.

And if you are really adventurous, and have access to a milling machine, you can buy a 0% forging and machine your own.
I'm working up my courage to start one of those