THE VFR PLT DEPARTED TULSA, OK, ON A FLT TO BRISTOL, TN, WITH A FULL LOAD OF FUEL. NO EN ROUTE STOPS WERE MADE. IN THE AREA OF BRISTOL, THE PLT CTCD TRI-CITY APCH CTL & REQUESTED RADAR VECTORS TO THE TRI-CITY ARPT. HOWEVER, THE ACFT'S ALT WAS LOW & RADAR CTC WITH APCH CTL WAS NOT MADE. THE PLT BELIEVED HE WAS SW OF THE ARPT, BUT ATLANTA ARTCC NOTED THE ACFT WAS 40 MI NW OF TRI-CITY. THE PLT WAS ADZD OF HIS PSN, BUT HE CONTD ON AN EASTERLY HDG. THE PSGRS NOTED TURBC, SNW SHOWERS & REDUCED VIS. SUBSEQUENTLY, THE PLT ELECTED TO LND ON A STREET IN DUNGANNON, VA. SVRL WITNESSES NOTED AN INTERRUPTION OF ENG PWR BEFORE THE ACFT WAS LNDD. RPRTDLY, THE ACFT TOUCHED DOWN HARD, THEN BOUNCED & WENT TO THE LEFT OF THE STREET, HITTING THE PORCH OF A HOUSE. THOUGH AN INTERRUPTION OF ENG PWR WAS RPRTD, THE PROP BLADES HAD EVIDENCE OF ROTATIONAL DMG. THE FUEL SEL WAS FND PSND TO THE RGT OTBRD TANK; THE 2 RGT TANKS HAD ABT 1 QT OF FUEL REMAINING. CG OF THE ACFT WAS CALCULATED TO BE BEHIND THE AFT LIMIT.