The non-instrument-rated pilot was on a cross-country flight when he encountered deteriorating weather conditions. The pilot was receiving flight following from air traffic control and, after discussing the weather conditions, he advised the controller that he was going to divert to a nearby airport. While en route to the airport, the airplane encountered increasingly lower cloud ceilings and the pilot elected to perform a precautionary off-field landing onto a county road. During the landing rollout the right main landing gear departed the road and the airplane subsequently impacted a ditch alongside the road. The primary fuselage structure and both wings were substantially damaged during the accident. A nearby airport weather observation station reported scattered clouds between 700 and 1,500 feet, an overcast ceiling at 2,100 feet, and a 5-mile ground visibility with drizzle.