Not being familar with your particular make of dryer, when you moved the drum; did you notice a small maybe 1/2 inch belt around the drum? These can break or slip off of tension pulley underneath drum. You may need to remove rear of dryer to see this. Also, as you stated it may need a motor. Can the motor be heard? Most dryers have a door switch, this could be defective.
Hope this helps
Walt
September 2008