Hey Rory!!!!! LOTS of people here on YT have flown to get their yorkies. I know Thorsmama just did last week. I think she said it cost $80 for the yorkie to fly back in her lap in a carrier. Send her a private message and I'm sure she can give you more specifics.
And you have GOT to tell me about this little puppy you might get! I'm getting too EXCITED over here!!!!