Where to get junk satellite dish?

I want one of those old, big, black mesh metal satellite dishes-- the ones that were about six feet in diameter. It doesn't matter if it's dented or rusty, and I prefer one that doesn't work. It doesn't need to have any of the electronics with it. I don't want to use it for receiving satellite signals (which may be obvious by this point); I want to use it to make a collector for a solar water heater.

I would like one as cheap as possible.

I would be willing to haul one away if anybody has one they want to be rid of.