I've always had such an attachment to pets put into animal shelters, just because they are essentially being put into pet jail for something that wasn't even their fault. They don't deserve the absolute abandonment of their owners at all. Many people don't want to adopt from shelters because they feel like there is something wrong with the cats and dogs inside.
Personally, I have 4 animals; 2 cats and 2 dogs. My family rescued all of our animals from the animal shelter, and we couldn't be happier with our decision. My mom worked at the Grapevine Animal Shelter for one year, and was disgusted with the people who would come in and dump their animals because "they moved into a new apartment that doesn't allow pets". She witnessed awesome pets be euthanized because the shelter would get too full. In my opinion, animals don't deserve to have their lives taken from them after only 2 weeks of living in a cold cage.
On the other hand, being in a shelter is not doom and gloom for every animal, but for the less desirable breeds and colors it could be their demise. You can find all great types of animals in shelters or rescue groups for a much cheaper price than breeders. Don't get me wrong, I'm not hating on responsible breeders, I just think it's unnecessary to purchase a puppy or kitten from a breeder when there are so many in dire need of adoption in shelters.
Now if you're making the decision to purchase a pet from a puppy mill, you are supporting the mistreatment of animals. Do your homework and research, and make sure you see the living condition of the animal you are interested in buying. Many people who run a puppy mill will have you meet them at a location that isn't their house to sell you the puppy. This is so that you don't see how awful they treat the animals that are there. If you are absolutely set on buying a puppy from a breeder, please make sure that the breeder is registered and reputable.
I am begging you to look at this situation differently if you are normally a shopper rather than an adopter. Your perfect pet is out there in a shelter, ready to start a new bond with you. Once you are willing to open your heart up, the animal shelter would be very pleased to have your business. These pets deserve a long, happy life with an owner who loves them unconditionally. You could be that owner.