Alternatively, contact Crimestoppers anonymously on 0800 555111 or via www.crimestoppers-uk.org.
South Western Ambulance Service sent three rapid response vehicles and one ambulance. A spokesperson for Dorset and Wiltshire Fire and Rescue Service said the driver was cut free from the car.
Police Sergeant Phil Lee, of the traffic unit, said: “I am appealing to anyone who was travelling along the A31 and witnessed this collision to please contact Dorset Police.
The A31 was closed for nearly six hours in both directions between the Bere Regis roundabout and the Roundhouse roundabout while emergency services dealt with the incident and collision investigators examined the scene.
The driver of the Volkswagen, a 55-year-old man from Southampton, was pronounced dead at the scene. His family have been informed and the coroner notified.
All three emergency services and an air ambulance were called to the scene of the collision at the White Post junction near Bere Regis just before 10.30am this morning.
The driver of the coach, who did not have any passengers on board, received minor injuries and did not require hospital treatment. The driver of the skip loader was uninjured.