There is a member here by the name of "VeritasForge" that builds excellent custom cases. Give scott_fx a chance to read this and he will back up this guy. Makes great work. Do a search on his name, and you will find his awesome work. Also makes full knights armour, so if you need some cool protection! Protects you from meteors!
Also "protocase" is another website. I haven't seen any of their work though.
There is no section devoted to just custom cases, but search for these guys and you will find some specific threads with links to other threads with what you want.