DC-10 CREW LNDG MEM FIND OPERATIONS INTO THE ARPT SOMEWHAT CONFUSING BECAUSE OF SIMILAR CALL SIGNS AND EQUIP FAILURES.

Narrative

MEMPHIS WAS LNDG RWY 36L AND R. WE WERE TOLD ON INITIAL CONTACT WITH MEMPHIS APCH TO EXPECT RWY 36L. WE WERE TOLD THAT RWY 36R WAS POSSIBLE. FO WAS FLYING. WE WERE VECTORED TO DOWNWIND; BASE AND INTERCEPT FOR RWY 36. ILS WAS TURNED AND IDENTIFIED PROPERLY. THE FINAL CTLR HAD A FEMALE VOICE. THERE WERE TWO OTHER ACFT WITH SIMILAR CALL SIGNS. OUR'S WAS ACFT X; ALSO ON THE SAME FREQ WAS ACFT Y AND I BELIEVE ACFT Z. A NUMBER OF TIMES PEOPLE WERE STEPPING ON OTHER PEOPLE'S RADIO CALLS AND ANSWERING CALLS FOR OTHER ACFT. WE LOST THE LOC SIGNAL FOR RWY 36L AFTER BEING CLRED FOR THE APCH. I NOTIFIED FINAL APCH CTL AND THE FEMALE CTLR CLRED ME TO RWY 36R; WHICH I WAS HESITANT TO DO BECAUSE OF THE PROX OF OTHER ACFT ON FINAL TO RWY 36R. A MALE VOICE INTERRUPTED AND SAID WE WERE AGAIN CLRED TO RWY 36L REDIAL FREQ AND 'IDENTIFIED.' ABOUT A THIRD OF THAT WAS DOWN THE GS ON COURSE AND ON GS. THE FEMALE CTLR GAVE US A 270 DEG HDG FOR RWY 36L AND NO ALT. I REQUESTED AN ALT AND SHE GAVE US ONE OF 3000 FT. CAME BACK AROUND TO RWY 36L NO PROB.