Ok Now that you have choosen your Breed

Now its time to start doing your searching. Go on the internet and type in the breed of dog you are interested in.
There are many sites out there for you to look thru, Examples are AKC, CKC, Breeders.net, Puppyfind.com, K9sud.com,nextdaypets.com,and my site www.Beesntees.com There are other sites like Kijiji.com, your local classified ads, there are many sites to look thru. 
Start emailing some of the sites that have your breed of Puppy, and wait for their response. 

One of the things you need to decide is if the puppy needs to be registered somewhere, like AKC, CKC, or one of the other organizations. If you want a pure breed make sure the person is willing to show you the parents of the dog. Also, they should have a website, where you can look around to see some puppies that they have sold, see the parents on line, see a little about them. You dont want to buy from someone who just let two dogs have some fun and now they are trying to make some money.  Go to someone who has years of experience, someone who takes the time and treats this like a business, not a hobby. Go to their website, really look around, make sure
they have plenty of pictures, When you email them make sure they get back to you quickly, if not than they most likely do this on the side as a hobby. When you email them ask them questions the more questions you ask the better. I say email is better because you have it in writing and you can read back what they say. 
Make sure the person is for real not someone scamming people. Thats why its important to do your research. 
Take your time dont rush  into a major life changing decision, you want to make sure you get the perfect family pet for your family.