My neice was married last year, Oct 1. She and her husband recently moved to Florida (I'm in NC). Their topper cake is in my freezer and she wants it for their anniversary. It is regular cake with buttercream icing. Any suggestions on getting it to her. No one is driving before their anniversary.

I could wrap good but would it survive if mailed?

It is going to *cost* to ship it overnight air. If you are willing to pay the price it can be done.
Put it in a sturdy box as close in size to the cake as possible; & has a window so everyone can see it is delicate. Mark the box in BIG letters ""CAKE - fragile!!".
Put pieces of styro inside the box where ever the cake/board is not - to keep it from moving around.
Keep it fzn as long as you can before taking it to the shipper.

ohh i want to ship one soo bad to my family in florida!!! i need help with that too but my cakes are fondant!

You can also try putting dry ice in there to keep it frozen for the trip. And of course package very well.

Fondant cake ship better than b'cream. The pkg'ing is basically the same.
I didn't mention using dry ice because it is hard to find in many areas but yes, that is a good idea.
Also using fzn ice packs would help just a bit.

On fondant cakes, the less decorataions used the better....ones that are flat on the cake should do fine but only thing that sits above will be a problem (like a flower corsauge). Put cotton or thin, sheet styro whereever you can if there are 'loose' decorations.