We have found two good sources for booking quality small guesthouses and Bed and Breakfasts on the web. (Note that such accommodation is called a "Pension" in German). These are:
Generally you need to book a cottage or an apartment for 3 or more days, probably a week in high season, but for a family with young children this can be a great way of enjoying the area. We would recommend that you choose a town and then use our Swiss Route links to find local apartments or cottages.
The suppliers of campsite information are