Where can I find a Yorkie Terrier puppy for less than 600 in the south suburban area of Illinois?

Sure, a Shelter. And they'd love to have a home all their own.
shelter dogs are much more appreciative. They've been to the Shelter and know what it's like. A forever home is sooo much nicer.
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SHELTER!
dont waste your money on a dog when you can adopt a perfetly normal one that actually NEEDS A HOME!
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try craigslist.com!!
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going to look at getting a cage from an ad i posted!!

At a local shelter or rescue. You might find some breeders who sell pups at $600, but that would be the bare minimum a reputable breeder would charge. I would expect that the price is closer to $800-$1000.

If you are on a budget, I hope you can afford all of the necessities of keeping a dog, including emergency vet bills. Not saying that you can't… just throwing that out there as a consideration. Many people bring dogs into their homes and then panic when they don't have the money for vet care.
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Because BreedX is 'Cool', was in a movie you saw, is unique and exotic, is free/cheap, or other such nonsense . . . One of the WORSE reasons to get a dog, or any other animal, for that matter, is because of their physical appearance or popularity due to a movie, TV show, or other publicity. Often, these venues feature exotic, rare or unique breeds that are, in the overwhelming majority of pet situations, unsuitable as companions. This visibility may also draw out those 'breeders' whose primary motivation is profit versus health, temperament, structural soundness and the welfare of their dogs.

And, remember to incorporate the same thoughtful consideration on whether or not to get a dog, and which breed or mix, when your friend, coworker or relative offers you one of Fluffy's puppies. Dogs are never really 'free' or 'cheap' and, in reality, require significant financial, physical, time, and environmental resources. At a minimum, none of these, or other such reasons, are sound selection factors for getting a dog and selecting a particular breed or mix. And, remember, if it is difficult for you to find information on a particular breed, or a breeder of the breed, it follows that you will most likely also have difficulty finding local support services that are familiar with the training, health care, and maintenance needs of that breed.
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shelter or rescue is the only place to go for that price http://www.petfinder.com
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