CONGRATULATIONS... on getting your new baby.
I'm in the same position as you are .except i've already got my yorkie this past weekend. I, too have another dog and right now i'm having problem getting them to play together. My bichon just refused to even gets near him. everytime i try to put them face to face the yorkie would try to bite and the other one will bark and hide away. its kinda frastrated cus i have to take them out separtly.
I even tried what Hugs suggested about letting them stuffed each other behind.
Still doesnt work. My bichon just dont want anything to do with my yorkie.
GoodLuck with yours.