Hello, Gary!
When we travel to Walt Disney World resorts, we
always send ourselves a package with items we'll find useful during our stay (especially when we're not checking a bag and need sunscreen!)
All you need to do is get the mailing address of your resort
on Walt Disney World.com, then ship the package to that address, with "Attention: Gary..." on it. (We put "Guest" in parentheses as well, just to be sure.)
If your resort has a Business Center, the package will available for pick up there. If not, ask about the delivery upon check-in; the Cast Member at the desk will be happy to explain where, when and how you can pick up your package at that particular resort if it's not already waiting for you at the front desk.
Enjoy your stay at Walt Disney World, and feel free to send us any additional questions you may have regarding your upcoming stay in the magic!