On January 26, 2001, at 1053 Eastern Standard Time, a Mooney M-20, N9558M, was substantially damaged while landing at the Mallory Airport (WV12), South Charleston, West Virginia. The certificated private pilot and passenger received minor injuries. Visual meteorological conditions prevailed for the flight that departed Summersville, West Virginia, destined for WV12. No flight plan was filed for the personal flight that was conducted under 14 CFR Part 91. According to the pilot, he arrived at the airport and serviced the airplane with 10 gallons of fuel. The pilot started the engine, and let it run for awhile to ensure it had warmed up because of the cold temperatures that morning. The pilot checked all the gauges, found no anomalies, and then departed. During the flight, the pilot preformed several touch-and-goes at several different airports before proceeding to WV12. Approximately 1 hour 15 minutes into the flight, and while operating on the left fuel tank, the engine began to "sputter". The pilot selected the right tank and the engine returned to smooth operation. When the engine started to "sputter" the left tank indicated 1/8. At the time the pilot switched to the right, it indicated 1/8 of a tank. The pilot became "very concerned," so he requested radar vectors to Charleston, West Virginia. While en route to Charleston, the pilot realized he was close to his planned destination, so he then requested vectors to WV12. Within a "few" minutes the pilot identified the airport, and maneuvered the airplane to land on Runway 33. Once on final, the pilot selected approach flaps, but they did not extend. With the throttle completely retarded, the pilot started executing "S" turns to maintain a proper descent rate. On short final, the pilot noticed that the airplane was right of the runway so he turned left, and then started a flare to land. The airplane touched down on the runway, but then departed it to the left. When the airplane departed the runway, the pilot had the controls all the way to the right. Before coming to a stop, the airplane struck a hangar and a parked airplane about 500 feet past the approach end of the runway. Except for being unable to extent the flaps, the pilot did not report any other failures or malfunctions with the airplane or its systems. According to a Federal Aviation Administration inspector that responded to the accident, continuity of the flaps system could not be verified because of impact damage.