It's hard to find because anyone can 'distress' furniture with a can of shoe polish, a toothbrush and a length of chain.
Beat the crap out of your furniture with the chain, then fleck it with the toothbrush dipped in shoe polish to simulate years of fly poop and you're good to go.
Like DangerMouse said, you can distress furniture yourself. The first step is to learn how to tell the difference between real wood, wood veneer, and the new particle board and contact paper crap being sold as furniture. Real wood is your best choice. Veneer is doable. But don't waste your time on the particle board/MDF stuff.
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