There is plenty of great accommodation available in the Cambridge/Karapiro area for a great range of prices.
Below is a list which includes some local accomodation directories as well as some individual accommodation providers:

Cambridge & Lake Karapiro New Zealand Accommodation, Event & Information Directory

Karapiro Willows - Luxury B&B

Gulley Retreat Karapiro You may even be able to bring your pet, but do enquire first.

Holiday Homes in Lake Karaprio - a selection of houses and cottages for you to look over

Lake Karapiro Lodge - "A well balanced combination of luxury retreat and unpretentious hosted service"

Jason's list of various kinds of accommodation in the Cambridge area

Oar and Paddle Boutique accomodation on the shores of the lake.

Hydro Road Affordable accommodation near the lake