I am wondering if there are any mods that allow you to turn into a werewolf of other creature

There's a werecroc mod, I'll link it if you want. It's on PES.

Yes.
http://www.gamesas.com/index.php?/topic/1113404-wipz-curse-of-hircine-resurrected/page__p__16336154__fromsearch__1&#entry16336154 Bugged, but a new version is worked on.
http://planetelderscrolls.gamespy.com/View.php?view=oblivionmods.detail&id=2000

Just do a search for Werewolves, Werewolf or Lycanthropy on TESNexus or Planet Elder scrolls etc. There are a few yes.

There wolf! There Castle!

There's a new werewolf mod on the nexus called http://www.tesnexus.com/downloads/file.php?id=34432.