Hi!
Is she spayed? If not that would be one thing I'd get taken care of right away. I'm not sure how much the vets in NY push the Lepto shot, but I would recommend not getting that. It is not required and Yorkies can have a lot of problems with it. Do a little searching on here for threads that talk about it. You can also do an internet search for Lepto and you'll find a lot of info there too. None of my have ever, or will ever, get that shot.
Other then that, I think just be prepared for her to maybe be a little depressed acting. She's use to having another dog and kids around. Take her on as many walks as you can to help bond with her. Walking is the best way to bond with them. Give her room to explore and get settled in. Try your best to let her initiate the contact at first. Whenever I got an adult dog, I always made sure I had treats with me so that whenever they did come to me I had something good to give them.
Read as much on here as you can. There is soooo much great info on this site. Ask as many questions as you want, we all love to share our advice and experiences. And please post pictures as soon as you can!