AT 0638 PST, THE PLT RECEIVED A WX BRIEFING ON A FLT TO SACRAMENTO, CA, AND WAS ADVISED THAT VFR WAS NOT RECOMMENDED. AT 0800, HE RECEIVED ANOTHER BRIEFING & FILED A VFR FLT PLAN TO PALM SPRINGS, CA. DURING FLT, HE ADVISED PALM SPRINGS TOWER THAT IF HE COULD GET THRU THE WX, HE INTENDED TO CONTINUE ON TO SACRAMENTO. RADIO & RADAR CONTACT WERE LOST APRX 7 MI WEST OF THE ARPT AT 2500 FT MSL. WHEN THE ACFT DID NOT ARRIVE AT ITS DESTINATION, A SEARCH WAS BEGUN; HOWEVER, IT WAS NOT FOUND UNTIL 9/13/83. THE ACFT WAS FOUND BY HIKERS APRX 15 MI NORTHWEST OF REDLANDS , CA AT AN ELEVATION OF ABOUT 6600 FT. AN EXAM OF THE WRECKAGE REVEALED THAT THE ACFT HAD CRASHED IN AN INVERTED, NOSE DOWN ATTITUDE IN MOUNTAINOUS TERRAIN. MOUNTAIN TOPS IN THE AREA RANGED FROM 10,831 TO 11,502 FT MSL. CLOUD BASES WERE REPORTED AT 2700 FT. ACCORDING TO THE PLT'S LOG BOOK, HE HAD FLOWN 5 HRS IN 1974, 1.4 HRS IN 1982 & 11.7 HRS IN 1983. THE CFI THAT CHECKED HIM OUT IN THE ACFT NOTED THAT IFR FLT WAS NOT RCMDD TIL HE RECEIVED MORE DUAL INSTRUCTION.