The Cromwell artist had used the bus as a peaceful retreat, installing a stove and creating a deck around it as well as housing some of her pottery.
Cockeram was contacted about two weeks ago by a member of the public who passed on a photo of the bus.
There was evidence of some activity around the bus, with other cars parked nearby, she said.
At first she was "very excited" that the bus had been found and she passed on the information to police via the 105 non-emergency reporting system.
A policeman visited the site about 10 days ago and phoned her while standing near the bus so she could verify unique features to confirm it was her bus.