A little over 5 years ago I began my search for a Yorkie. I have never shared this story before but have wanted to for quite a while and hope by sharing others will learn as I did from my experiences.
We previously had a Lab who was wonderful. Our neighbor had 2 unaltered dogs a female Black Lab and male Golden/Retriever mix~get the idea here. Abby was from their litter and I was very excited to have a puppy for my boys who are now 23 and 21. All I can say about this is that all the neighborhood children get lessons in SEX ED from their breedings~enough said about that. All of these puppies were advertised in the For Sale ads of the newspaper. They 2 more litter from Abby's parents and decided to stop when the owners of the second litter started to call asking if she was going to have more puppies soon because at least 2 needed to be "put down" because their hips were so bad. We had Abby for many year and she was a huge part of our lives. As my boys grew up she romped in the yard, went camping, fishing, whatever we did she went along and was their very best friend. When she passed away as they were entering HS and Megan was very little.
This was my first lesson with a BYBer-literally IN THE BACK YARD. 
So fast forward~a few years passed and my daughter who is now 14 yrs old wanted so badly a puppy~a Yorkie puppy.
At first I resisted, my husband was adamant and the boys really didn't care. But she kept Googling and showing me puppies~every day. She put an adorable puppy on the computer as a wallpaper with the words "I NEED him!" running across the screen. She was really working it!
I decided that maybe another dog wouldn't be such a bad thing and started to look around for breeders online. I really wanted to do this right. But the more that I looked and read the more confused that I became. Then one day she came to me with an Kijiji ad. There was a breeder in Shorewood advertising Yorkies. They were ADORABLE! The Kijiji ad had a link to their website. It had pictures of their family, a daughter that was about Megan's age (get my SN now
) holding the most adorable puppy that you could imagine. There were pictures of their home, a puppy nursery, story how they loved having puppies in their home and that the daughter and her friends all loved being involved. I was drawn back to their ads over and over for several weeks. Watching the ad, going to their website and buying into their story. I already had a puppy fund saving around $800 that seemed to be the going rate for a Yorkie puppy.
In my "research" I knew that I shouldn't buy from just anyone on line and that there were all kinds of evil puppymills that disguised themselves as loving "raised underfoot" breeders. I was NOT going to be tricked by them~so I decided to call the family in Shorewood to inquire about the puppies advertised. I had a list of questions and was prepared. I wanted to know about parents, age of the puppies, testing, you know the drill.
I make the call with knots in my stomach, list of questions in my hand and got the answering machine. A few hours later I got my return call and also a HUGE lesson. The nice man on the phone began by telling me that no all of the puppies that were advertised had been sold.
I asked about the parents and their temperament and he told me that the parents lived with a "really nice breeder in Missouri "
(puppymiller) 
But there were several others families
(puppy brokers) in this area that also had puppies from the "breeder"
(puppymiller) and that they all took turns driving down to Missouri to her Kennel
(puppymill) to pick up puppies. Did I want their numbers maybe they had some left.
I asked how often the "breeder" had litter of Yorkie puppies. He planned to drive down in about 2 weeks but had to wait until the new puppies were 8 or 9 weeks old. Did I want him to give me a call.
I will break it down:
The puppymill in Missouri had brokers all over the Chicago area. They would drive down to the mill and bring back Yorkies puppies about every 8 weeks to broker out of their homes. The supply was unending and if I was willing to wait a few weeks I could have an 8 weeks old that was sold to the broker by the mill. The brokers all took turns making the 8 hour trip and then divided up the puppies and advertised both on their own websites and Kijiji. They purchased the puppies for a couple hundred dollars and sold the puppies for around $800 which is less then the local pet shop.
Within a few months of this phone call I was asked if I wanted my friends Yorkie puppy (Pebbles). The "breeder" was a HS teacher and sold puppies on the side for extra cash to help pay her bills.
The puppy was purchased as birthday present for a 1 yr old and was AKC, 6 months old, and had pretty much been over looked for the past 3 months because well the 1 year old didn't want or know what to do with a puppy. They had paid $600 for her and were willing to rehome her to me free. Within days she was growling at anyone who walked near her food bowl, bit me on the back of my arm and I was told NEVER to bring her back to the groomer at Petsmart because she was aggressive and tried to bite the groomer.
and the cycle continues...................