Hi Marti,
 
I don't know of any inexpensive ways to ship your ferrets from Florida to
Michigan but I would recommend trying to take them on the trip with you.  If
that isn't possible I would look for someone that ships animals via air
don't even think about ground like UPS or any of those unless they
mostly/only deal with shipping animals.  They would probably die or get sick
on the way if you have UPS, or any of those ground package shippers do it.
 
Talk to you later!
Dan
[Posted in FML issue 1693]