Hey Amanda!
I'll tell you a couple of the things that we do!
Sometimes, my family actually ships a box to our hotel of things that we'll need while there. I include another flat box, return labels and packing tape. That way we travel lighter..especially with Airtran charging us if our luggage goes over the 50lb mark! I'm the lady at the Airtran desk praying and jumping up and down saying' " But...but...it can't weight that much!!"
When we arrive and check in I ask at the front desk if my package has arrived and they either hand it to me at the front desk, or it is already in my room , or they bring it to the room when it arrives. At the end of the trip I pack up the boxes and bring it to the front desk or Concierge for them to ship home to me!
Another good thing to know at Disney World is when you are checking out at any shop in Disney World ask the Cast Member about shipping your purchase to your home and they can take care of it from right there! Yay! How easy is that?
I have also been known to buy a cute new Mickey Mouse suitcase for the trip home to stuff cute new Mickey Mouse things in...ahem.
Have a GREAT trip!