I did all my fluids in August before driving cross country. Wasn't difficult at all with the minor exception of needing to remove the reinforcement plate to access the front diff.
As far at the tranny, I got my supplies and read all the instructions here:
California Transmission Supply
Hmm. It appears the instructions are gone now. I may have them saved somewhere.
No, they are still there. Buried a bit
About Oil
I don't recall where I got the transfer case fluid from right off. It was the most expensive per litre of any of the fluid.