Parker, There are many coves on and Bay on Winnipesaukee that would suit you fine....a couple of places to contact about rentals would be:
Strictly Rentals in Center Harbor
http://www.strictlyrentals.biz/
Preferred Rentals in Center Harbor
http://www.preferredrentals.com/
My family has Rented our place through Strictly Rental, and I therefore know that she has a pretty big selection of properties. And the line outside of Preferred on Sat. leads me to believe that they had lots of rentals as well. There is also the classified here on Winnipesaukee.com..... I would advise that you start looking and make your arrangements soon, places fill up quick...