I know that there are crocodile species native to the United States, but I though that mostly what you found here, particularly in Louisiana, was alligator. In any event, lots of different makers produce crocodile or alligator shoes. The best can be extremely expensive, while the worst look like pimp's shoes. People tend to think that crocodile and alligator leather is very durable, but they're wrong. It's fragile and prone to splitting. I think that crocodile or alligator shoes can be very attractive if done well, but cowboy boots are always a safer medium for those skins. Ostrich, particularly full-quill ostrich, is something that has to grow on you. I believe that ostrich leather is extremely tough, and like crocodile or alligator, it's usually better to save it for cowboy boots. Lizard can make beautiful cowboy boots, but I'd chop off my big toe rather than wear shoes made from it. I'd chop off my entire foot rather than wear any footwear made from python. In the semi-exotic-but-suitable-for-shoes category are peccary and shell cordovan. Peccary is the leather from a wild South American boar. It's grained similarly to deerskin, and it's similarly soft. However, where deerskin will scuff if you look at it funny, peccary is much tougher than calfskin. Gravati and Moreschi are both peccary specialists. Well-done shoes made from peccary can be beautiful: http://www.gravati.it/inglese/Image/4.jpg
Beware, however, some of Gravati's and Moreschi's more, ahem, exuberant creations that mix peccary with calfskin (or worse, with ostrich or crocodile). Shell cordovan is a kind of vegetable-tanned horsehide that is only produced by the Horween Tannery in Chicago. It takes a wonderful shine and it's extremely durable. Alden is the best-known shell cordovan specialist, but others, including Allen-Edmonds, Crockett & Jones, and Laszlo Vass, make shell cordovan shoes.