THE NON-INSTRUMENTED RATED CANADIAN PILOT RECEIVED A WEATHER BRIEFING, WHICH INCLUDED AN ADVISORY THAT VFR FLIGHT WAS NOT RECOMMENDED. HE FILED A VFR FLIGHT PLAN & CONTINUED WITH THE NIGHT CROSS-COUNTRY FLIGHT. THE PILOT CONTACTED BURLINGTON APPROACH CONTROL & REPORTED HE WAS 29 MILES EAST OF BURLINGTON AT 4500 FEET IN SNOW SHOWERS. RADAR CONTACT WAS NOT MADE & RADIO COMMUNICATION WAS NOT REESTABLISHED. ON 7/6/90, THE AIRPLANE WAS FOUND BY A HIKER ABOUT 40 MILES NORTHWEST OF THE BURLINGTION AIRPORT, WHERE IT HAD CRASHED ON THE EAST SIDE OF A MOUNTAIN. THIS WAS ABOUT 60 MILES FROM THE LAST REPORTED POSITION. AN INVESTIGATION REVEALED THAT THE AIRPLANE HAD FLOWN INTO THE SIDE OF WOODED MOUNTAINOUS TERRAIN AT THE 2000 FOOT LEVEL, HEADING NORTHWEST. AT BURLINTON, (ELEVATION 334 FEET), THE WEATHER WAS IN PART: 1600 SCATTERED, 3600 BROKEN, VISIBILITY 6 MILES WITH SNOW, WIND FROM 350 DEGREES AT 8 KNOTS.