You can check the rental places but better is the landscaper that has one mounted on a tractor and will come and rake for you.
They work great for removing small to midsized rocks but if you have ledge/big stones near the surface it will beat them up.
For the price you will pay for someone to do an acre or so of harley raking in 4 hours @ $75 an hour you might find a used landscape rake with wheels.
Also check CL for all these things - serivces etc..