Hi, yes use light chocolate or brown colored fondant, roll really thin, apply and distress it by using a knife, poke some tiny holes in it. Then dust all over with cocoa powder using a large, soft brush.
just cover it with white fondant, make scratches that you want and then hand rub cocoa all over it. I made a Sorting hat like that (Harry Potter) and it looked awesome.. I also did the same thing for a balance beam cake I did.
You can also purchase a small sheet of bumpy hard plastic covering made for flourescent lights at the hardware store and roll your fondant on that and dust with a little coco powder. It will make the fondant look EXACTLY like old leather.
Got that one from the doctors bag cake in a Collette Peters' book.
FINALLY...I got a few cakes uploaded. Feel free to critique...more coming.