I have a house on Cape Cod.. I love it here, and depending on how far you want to travel to experience the Cape, we could recommend some places for you to stay. Just remember this the summer on Cape Cod is very crowded, traffic jams galore, and not easy to get around.. For those of us who live here, we do our daily errands before the traffic gets heavy and then just sort of settle in at home or at the beach during the day.
Not too far from where I live there is an area called New Seabury that does rentals.. You could look under that name or Mashpee or Falmouth with a google search and find information on those areas.
Of course you can also go further into the Cape.. there are some beautiful towns, Brewster, Orleans, Truro, Chatham, Dennis, just to name a few.. look under any of these for information. Good luck..