SMA ENTERS TFC PATTERN IMPROPERLY AND HAS CONFLICT WITH AN ULTRALIGHT.

Narrative

I WAS APCHING PERRIS VALLEY ARPT; I WAS UNFAMILIAR WITH THE AREA AND VISIBILITY WAS MARGINAL VFR (ABOUT 3 MI). THERE IS A PARACHUTE JUMPING AREA E OF THE FIELD AND TFC IS RESTR TO W OF THE RWY. THERE IS ULTRALIGHT ACTIVITY S OF THE FIELD. I WAS AWARE OF THESE FACTORS; AND OBSERVED ULTRALIGHTS IN THE AIR WHILE LOOKING FOR THE ARPT. MY INTENTION WAS TO APCH FROM THE SW AND FLY A L BASE TO LAND ON RWY 33. HOWEVER; WHEN I FOUND THE ARPT; I WAS NEARLY OVER IT. THE ONLY WAY I COULD SAFELY MANEUVER TO AVOID THE PARACHUTE AREA E OF THE FIELD WAS TO TURN R; WHICH I DID. THERE WAS AN ULTRALIGHT BELOW ME ABOUT 500 FT AWAY WHICH I SAW AT ALL TIMES AND AVOIDED; ALTHOUGH I UNDERSTOOD FROM UNICOM LATER THAT I FRIGHTENED HIM BECAUSE HE WAS AFRAID I DIDN'T SEE HIM. I FLEW A TEARDROP S AND W OF THE FIELD; ENTERED A L BASE FOR RWY 33 AND LANDED. FIGURE 1 DIAGRAMS MY APCH AND THE POS OF THE ULTRALIGHT. IN THE FUTURE; I WOULD PICK A POINT WELL S OF THE ARPT AND TRY TO APCH THAT FROM THE SW; THEN OVERFLY RWY 33 AND ENTER A L PATTERN FOR LNDG.