That's not to say that hardware hasn't been photographed on the Moon, it just hasn't been imaged from Earth. From lunar orbit, I know that at least one Surveyor lander was imaged by a Lunar Orbiter back in the 60's:
http://nssdc.gsfc.nasa.gov …ject_page/lo3_h194_1.html
And I think another orbiter called Clementine imaged the Apollo 15 landing site and, while it couldn't quite make out the lander, it could see the dust it cleared away while landing.
Spy satellites are, of course, in Earth orbit. Some of the old Keyhole series were comparable with Hubble in mirror size but they were looking at the Earth, not the Moon. Modern spy sats can resolve about 0.1 meter or 4 inches. They can't read license plates, but they can tell if a car has one or not. I saw an interview with some old NRO guy and he said you can tell if a Russian sailor is wearing his cap or not!
When we get the Lunar Reconnaissance Orbiter in place later this summer, we'll be seeing 0.5 meter images that'll clearly show almost everything either we or the Ruskies ever put on the surface.
I know one of those nuts who think we never went there, and there's no convincing him or people like him!