You can find many smaller pups at shelters or rescue groups. If you have a particular breed in mind, check the rescue groups in your area. Do a Google search.
PLEASE do not buy one from a petshop or ad in the paper. The petshop ones are more then likely dogs from puppy mills with a host of problems and backyard breeders do not care who gets their puppies as long as they make money.
And please do not patronize the "designer" breeders either - sometimes I think they are worse then the puppymills/backyard breeders. They try to justify creating "mutts" for hundreds of dollars.
Take your time, pick the right breed for your lifestyle and read all about the breed and how to take care of a puppy.
BTW its better to get a puppy about 10 weeks old - too early and you'll have a lot more problems. And smaller breeds are sometimes a lot harder to housetrain then medium/larger breeds
