It's all one piece and does not come apart. They deliver it to your room in the box. I'm not sure, but I think the delivery charge was $7.50. You just save the box it came in and take it to guest services when you're ready to send it home.
Now for the downside....
We loved the tree and I'd do it again, BUT I was very disappointed in the shipping done by WL. They had told me they would "prepare" the package for shippping. I took that to mean they would pack it properly. So, I just took the tree sitting in the box down to guest services and filled out the paperwork and left it. I should have checked into the shipping better. They did no preparation at all. They basically put a label on it and sent it UPS.
The box got crushed in shipping and several of the ornaments were broken. To WL's credit, they reimbursed us for the damaged ornaments, but it was a hassle taking care of it. UPS wanted to refund the entire tree and take the tree (that WAS NOT going to happen

) and so we just dealt with the WL.
When I first called WL about the damage, they said that they don't have packing materials available to them, so be aware this is something you'll need to discuss with the florist or the resort you're staying at. Had I known this is how they were going to ship it, I'm sure I could have talked to someone that would have figured out a way to do it properly. I'm quite positive that in all of WDW they have some shipping material.
It is a separate number to order the tree. The number is 407-827-3505. As I understand it, they area separate business, but affiliated with WDW. They have a website as well, but it's not very informative as far as the trees are concerned.
I'm working on those pics!
Sorry, meant to include that website link...
http://www.disneyflorist.com/