DMA,
This is a hit and miss thing, but if you have schools or colleges in your area, you might keep an eye out for any auctions. Since they're not specifically foodservice auctions, they don't always attract the used equipment dealers. I had a friend that purchased an commercial electric range for $25, and a Hobart double stack electric convection oven with digital controls for $50. Granted, electric isn't ideal unless you have a unique situation, but he ended up selling that range for about $100, and the convection oven for $300. He sold both to a used equipment dealer, who I'm sure sold them to someone else for a further markup.
Just a thought.