Make friends with the local Redneck Underground, you know, the tradesmen that can be found at bars every Friday night. They know people who know people, cash or beer goes a long way, or trade stuff. Roofers, plumbers, and scrap dealers are the places to go for soft lead these days and if you put your feelers out and build a reputation as "that guy who pays for lead" you will be surprised how much stuff starts showing up.