Quote Originally Posted by cleancloths
I would suggest you go back to square one. Turn off the main breaker to the house and see if you still measure a voltage - that will rule out your electrical system. If you still do, then turn the main on and all the other breakers off, is it there? If not, turn on one breaker at a time and take measurements. It might be an open neutral on one circuit or a ground/neutral reversal somewhere.
I am an electrical contractor and I would have to agree this is the best way to start. If it doesn't locate your problem (but it should) then drive the ground rod.