I just went through this and even have my own thread on it:
http://www.yorkietalk.com/forums/gen...kie-puppy.html
however I am dealing with 2 Yorkies. Time is going to make it better but you need to make sure Zoey knows shes first in your eyes. No need to do outside introductions. Make sure everytime you come home, you say hello to Zoey first and then give your new guy attention. Also Yorkie pups are full of energy and tend to be intimidating to older dogs, so it is best to make sure you keep a close eye on your new pup and make sure he is not jumping all over Zoey. I still have a ways to go but it is amazing what positive changes have occurred over the last month. Also, dont force the situation, they have to come to accept one another on their own. Best of luck to you and your furry kids. Post a pic if you can.