PLT OF A PIPER COMANCHE PA24-250 ENTERED CLASS C AIRSPACE; APCHED AND LANDED AT THE WRONG ARPT DUE TO DISORIENTATION.

Narrative

I WAS ON A TRIP FROM F39 TO OUN IN VMC ON THE MORNING OF AUG/WED/00. 5 MINS AFTER DEP; I REQUESTED AND RECEIVED FLT FOLLOWING. FROM ZFW XFERRED ME TO OKC APCH ABOUT 20 MINS FROM MY DEST. ABOUT 10 MINS OUT THE CTLR TOLD ME TO DSND AT MY DISCRETION AND THAT THE CTL TWR AT OUN DID NOT OPEN UNTIL XA00 AM. I BECAME CONCERNED AND PREOCCUPIED WITH FINDING THE CORRECT FREQ TO CALL MY POS FOR THE TFC AT MY DEST. I LOOKED DIRECTLY OFF OF MY NOSE AND MADE VISUAL CONTACT WITH AN ARPT I DETERMINED TO BE MY DEST. IN THE TIME I WAS PREOCCUPIED I HAD OVERFLOWN MY DEST AND MISTAKEN WILL ROGERS FOR OUN. I HAD CHANGED MY FREQ TO 118.0 FOR OUN TFC WITHOUT THE PERMISSION OF THE CTLR. WHEN I ENTERED THE TCA; I WAS SQUAWKING THE FLT FOLLOWING FREQ AND MY RADIO WAS SET AT 118.0. THIS MISTAKE WAS DUE TO MY LACK OF CONCENTRATION ON MY POS AND NAV. I ALSO SHOULD HAVE HAD A FLT PLAN FORM FILLED OUT AND PLACED ON MY KNEE BOARD SO I KNEW THE RADIO FREQ LONG BEFORE MY ARR. I HAD A GARMIN 195 MOUNTED ON MY YOKE; A CG-20 CHART AND MY FLT DIRECTORY. I ASSURE YOU THIS MISTAKE WILL NOT HAPPEN AGAIN. THERE WAS ANOTHER ACFT ON FINAL FOR THE CROSS RWY. I FELT I MAINTAINED THE REQUIRED SEPARATION AND DETERMINED I COULD LAND WITHOUT INTERFERENCE. I WAS CALLING MY POS BUT I WAS ON THE OUN FREQ 118.0.