I'm in the UK, born and raised in the Midlands, where the greatest concentration of Kimberleys resides.
It's not a very common name, but not exceptionally unusual. It's generally held to be linked to the Norman Conquest of 1066, so it goes back quite a way! My own theory is that the name derivees from the Breton town now called Quimperlé.
I expect to post some more information in the near future. Feel free to mail me.