Well technically the Shivering Isles are a plane of Oblivion and there are a lot of mods that change it.
/smartalec
I was thinking of saying something like that and using it as an excuse to mention Integration, but I decided not to.
If you just like the aesthetics of the Deadlands you could always try some quest mods that take place in the Deadlands; like:
Dremora Companion
Dramask? (I know thats not the right name, it's that one Dremora city mod)
Servant of The Dawn
Integration does have a pretty nice "ordered" Deadlands realm, but that's pretty small and it's late in the quest line..
Hmm, I wonder....
http://www.tesnexus.com/downloads/advancedsearch.php
plane has 65 pages of results
planes has 7
Daedric has 97
realm has 54
Dagon has 14
deadland has 1
Nothing that adds more to the random deadlands list, but I did see some interesting stuff when I was randomly looking through the resultd, like an Oblivionized tamriel, and a moonshadow realm mod