I wish you the best in all your new-to-come Yorkie endevours! When Trixie has her pups in Oct, it was her/my first litter too...I think most everybody knows that by now.
Like you you are doing now, I did ALOT of research and worked with our vet and other breeders first. I will tell you the one thing that helped me the most was actually being present for whelping before it was our turn. I wasn't as nervous as I think I would been had it been the first time and I knew what to expect, signs of nesting, etc. I have not regretted my decision at all...it has DEFINATELY been worth every minute! It is the most rewarding feeling I have ever felt...next to giving birth to my own daughter, of course
Good luck! You know your YT family will be here to help you along the way!