I shot some 9mm this week that cost less than a buck fifty a box. The bullets were given to me by someone who got out of reloading. The powder was given to me when I bought a reloading press from someone who was getting out of reloading. I scrounged the brass at the range. The only cost was my time and the primers...just sayin'.
I picked up a few bricks of it at the last 1500 for $5/20...and I think he'd give you a further price break if you but a bulk pack, but I don't remember how much. I haven't been to this show though. Other than that I think most ammo can be bought online cheaper than anywhere I've found on a regular basis
I just picked up some ammo at Duhnams recently. They had 15% off all handgun ammo. They had Hornady Zombie Max 165 gr. marked down to $21.99 a box and I got an additional 15% off that. Had I had more cash on hand, I would have picked up some more range ammo too.