For our packages to POP, we were instructed by the front desk to address them as such (using Jack Sparrow arriving on June 1 as an example):
Jack Sparrow, GUEST, Arriving 6/1/07
c/o POP CENTURY Resort
1050 Century Drive
Lake Buena Vista, FL 32830-1000
They requested GUEST and ARRIVING info to be in the first line of the address, versus the comment area (say if you are ordering from an online vendor) so it is very clearly displayed. We were told the Confirmation number is not necessary.
Hope that helps.