SMA IN UNCTLED ARPT TFC PATTERN HAS NMAC WITH SECOND ACFT.

Narrative

AT 10 NM FROM THE ARPT; I CONTACTED UNICOM; AND WAS TOLD THE ACTIVE RWY WAS 35. I WAS ENTERING FROM THE E; SO I ANNOUNCED ENTERING R DOWNWIND FOR 36 AT A 45 DEG. I LISTENED AS A HELI TURNED R BASE TO FINAL; AND LANDED. BECAUSE THE HELI WAS ON THE THRESHOLD; I EXTENDED MY DOWNWIND APPROX 1 MI; AND PROCEEDED TO DSND. I ANNOUNCED WHILE TURNING R BASE; AND WAS TOLD BY ANOTHER ACFT THAT TFC WAS L-HAND AND I WAS TO 'GAR.' I LIFTED MY WING TO CLR BEFORE STARTING MY CLBOUT; WHEN I SAW ANOTHER HIGH WING ON FINAL; APPROX 150 FT TO MY L AND 50 FT ABOVE. THIS ACFT HAD NOT CALLED HIS POS; EXCEPT TO SCREAM AT ME OVER THE RADIO. AFTER I BEGAN EVASIVES. I BELIEVE THAT THIS SITUATION COULD HAVE BEEN AVOIDED IF THE OTHER ACFT WOULD HAVE NOT ONLY ANNOUNCED HIS INTENTIONS AND POS BUT ALSO USING SOUND JUDGEMENT IN ALLOWING SPACE BTWN US. I ALSO FEEL THAT; IF UNICOM GIVES ACTIVE RWY INFO; THEY SHOULD STATE WHETHER R OR L-HAND TFC IS BEING USED; OR IF THERE IS A PREFERENCE. I ALSO BELIEVE THAT THIS COULD HAVE BEEN AVOIDED BY MORE ACCURATE SCANNING METHODS ON MY PART.