Well, nrabinowitz was right. I tested it more on my own server using proxies, most timed out, some returned the above error, and a couple returned correct results (well I assume they were correct based on the location the IP address of the proxy - because the figures were a little different than using my ISPs public IP address (calif., USA)).
So it's simply a matter of google blocking certain types of requests from certain IP addresses.
Thanks again for the comment.