I don't know anything about making targets, but I purchased some through http://www.arntzentargets.com/index.htm
(Good AR500 steel).
I hung them from those cheap plant hangers you buy at Walmart for $5 and they seem to work great. Most of the rounds end up on the ground right below the target as far as I've been able to tell. I just throw a fresh coat of spray paint on them when I'm finished. (I like the self healing reactive targets from Academy too... you can see one in the background.
Gen 4 Glock 19, Taurus 24/7 pro CDS .40S&W, Taurus TCP, S&W 22A-1, Remington 870.