Here is a great website with lots of information about showing and dog show schedules.
Lacy's Place in Cyberspace - Dog Show Information
I would start by attending a dog show and if you decide it is something you want to do then you will need start your search for a show dog. If you already have a dog that you feel is show quality then I would recommend you contact a show breeder or handler and get your dog evaluated. It required a lot of time and effort to grow a proper show coat on a Yorkie. If you have any specific questions we would be glad to help.