The power loss occurred in cruise at 10,000 ft. At 0903 EDT the pilot notified Wilmington Approach Control that he had a 'rough engine' and requested vectors to Wilmington. Approach Control responded with heading information for the back course approach and a descent to 1,600 ft. After initially telling the controller of the engine trouble no further mention of engine status was made by the pilot. At 0906 the pilot transmitted that he was looking for the approach plate and asked for the localizer frequency. About 3 minutes later, after being given the frequency, the pilot was informed by the controller that he was going through the localizer and given a heading change. The pilot stated that he extended the landing gear at 4,800 ft because he did not know how far he was from the airport. Twice during the approach the pilot was advised of his distance from the final approach fix. The aircraft impacted trees approximately 2 miles from the airport.