Hi, Peggy!
Congratulations on your princess' birthday -- what a fantastic celebratory vacation you have planned! If you're talking about purchasing items online from
DisneyStore.com and having them shipped to your Disney resort room or Disney cruise stateroom, it's possible. Just let me offer a few tips and caveats!
My friends, Dave and Jennifer Marx, have a helpful website and guidebooks -- PassPorter.com and the PassPorter's series. They offer up-to-date information on shipping items to both your Disney resort as well as to your Disney Cruise stateroom. (They test this kinda stuff out all the time, and it's been a while since I did this.) You'll just need to search it on their site or on their discussion boards. In addition, I would encourage you to send it to your resort and make contact with a Cast Member there. Although you can have items shipped to Disney Cruise Line, shipments are sometimes delayed. If there are complications in shipping or holding, the resort doesn't move -- if you get my drift! Also, make sure DisneyStore.com should be aware that you're shipping it to your resort, and they should mark it with instructions to hold until your check-in date.
I hope all that makes sense, and please write back if I can provide more direction for you. Thanks for your question here on the Disney Moms Panel, and I hope you have a wonderful day and a magical vacation. Bon voyage!
Andi