C210 PLT LANDS ON THE PARALLEL TXWY AT TUS.

Narrative

I WAS ON A VFR FLT FROM BLH TO 5T6 AND ENCOUNTERED DETERIORATING WX AND MADE AN UNSCHEDULED LNDG AT TUS INTL. WX WAS A CONTRIBUTING FACTOR. WHILE BEING VECTORED; I FOUND IT NECESSARY TO DSND BELOW 4500 FT TO AVOID SMALL; PATCHY CLOUDS. VISIBILITY WAS RPTED TO BE OVER 5 MI; BUT IT WAS POOR BECAUSE OF RAIN AND POOR LIGHT. I DID NOT PICK UP THE ARPT UNTIL I WAS WITHIN 3 MI OF IT ON A 45 DEG L BASE FOR RWY 11L. TXWY A STOOD OUT AND LOOKED TO ME TO BE RWY 11L. IT MAY HAVE STOOD OUT BECAUSE IT WAS THE CLOSEST. AS I TURNED FINAL; I WAS ADVISED OF ANOTHER PLANE LNDG ON A PARALLEL RWY. AT THAT TIME; IT APPEARED TO ME THAT EVERYTHING WAS IN ORDER. THE THINGS THAT I SHOULD HAVE DONE TO AVOID THIS INCIDENT ARE: 1) I SHOULD HAVE REQUESTED AN IFR CLRNC; GIVEN THE WX AND MY LACK OF FAMILIARITY WITH TUS. 2) I SHOULD HAVE DIALED IN THE RWY 11L ILS. 3) I SHOULD HAVE CHKED THE ARPT DIAGRAM AND NOT THE INSET ON THE APCH PLATE IN THE 'TERMINAL PROCS.' 4) I SHOULD HAVE MADE SURE I PICKED UP THE RWY NUMBER INSTEAD OF THINKING I SAW IT. I MADE A BAD MISTAKE AND I WILL NOT MAKE IT AGAIN!