It is now possible to stay in Grantchester either at:
Manor Farmhouse which offers bed and breakfast accommodation tel: 01223 842338 or email john<at>manorfarm1.plus.com.
The Blue Ball Pub on Broadway also operates a Bed and Breakfast.
There is also plenty of accommodation in and around Cambridge. Two nearby options in Trumpington are: The Lord Byron Inn, and (newly opened to B & B) Anstey Hall . Here is a link to Cambridge Tourist Information’s accommodation page.