Cant offer you any specific detecting hot spots but I always encourage diggers to sweep any place they dig, even paleo sites...never know what other diggers may have lost 100 yrs ago...OR, high on my wish list...to find a METORITE in a camp site that some young brave had brought home to show Mom .
Well, metal detecting is far more difficult that I think. Besides owning a good metal detector, the most important thing is that you should be very patient. Because you will find much more scraps than treasures.