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There are some books about Yorkies out there but I have never read them. I don't think those books could come close to the information found on this website.
I have never heard of shaving puppy hair off. Puppy hair falls out and is replaced with the adult coat. You can get your pup groomed however you want. If you like the adults in the show cut, do it. If you like the shorty puppy-cut look, do that. My Yorkie has wavy-crazy hair, so she is usually in a puppy cut (growing her out now though). Quite a few of us do grooming ourselves. It is cheaper and we don't have to worry about abuse and neglect when leaving them with a groomer. Whatever you are comfortable with... You can always ask to stay and watch though.
The Yorkie standard calls for upright ears. Ears that don't stand up are cute though. You can tape them up if you want or let them hang. It is your preference. If you plan to show they have to stand. Ellie's ears stood without taping. They came up on their own.