Hello David,
Shipping a package to a Walt Disney World Resort is quite simple and I have done it often.
1. Call Disney's Resort Hotel Reservation line, 407-939-1936, and have them make a note on your reservation, a package will be arriving.
2. While on the phone, ask for your Walt Disney World home away from home resort's mailing address and phone number, or look on your Walt Disney World resorts home page under Resort Overview. Addresses and phone numbers can be found on the right side of the page part way down under the resort map.
3. On the Shipping Label and Package, clearly mark the word "GUEST" and your "ARRIVAL DATE." I like to write "Guest" and my "Arrival Date" ALL over the package so it is sure to be found and I even go so far as to decorate it with some Disney stickers, this way it is easily recognizable.
4. Plan to mail your package so it arrives a couple of days before your arrival date, pay for tracking if like.
5. Call your Walt Disney World home away from home resort a couple of days before arrival to confirm it has arrived.
If I can be of any further pixie dusted assistance feel free to ask and may your upcoming stay be filled with many magical and memorable moments.
Amy M*o*