Well this is a hard question.
A lot of this is in personal preference. What kind of dogs do you like, and why? Browse some breeds online and see what you think. When you have a few breeds in mind, do your research. Research the breed as much as possible. What's the breed's history, what were they originally bread for? Breed characteristics are important when training a dog. Herding breeds can be more prone to nipping, terriers may be more likely to dig and hunt for small animals in your back yard, and sometimes non-sporting breeds can be difficult to motivate for training. Once you learn more about a breed you're interested, ask yourself again, is this the type of dog I want, and why?
Don't fall into the, I want this breed because I think they're cute. That's the worst possible thing you could do! Figure out what you really want out of dog.
Look at your own life as it currently is. What's YOUR energy level??
Are you a high-energy person that goes running every morning, or does it take you 30 minutes to wake up while you slowly sip your coffee? Most dog's energy levels falls into 4 LEVELS: low, medium, high, and very high. You should always adopt a dog that is AT or BELOW your energy level, NEVER above! Does the breed you picked match your general level of energy?
Once you have decided on a breed(s) you like and think would fit well into your home, it's time to decide where you could get your new pet from.
You basically have three options:
1. Your local shelter or rescue.
3. Pet store
1. I would highly recommend you choose one of the first two options. It is best to adopt from your local shelter whenever possible. You will not only be getting a new addition to your family, but helping out an animal in need. Also when considering adoption, shelters offer many different age groups for adoption. Perhaps you would like to skip the puppy potty training stage and adopt an adolescent dog. It's always nice when someone considers adopting older dogs as well, many are already trained and at a lower level of energy. Another great thing shelters offer is variety. I firmly believe that mutts are the way to go! Mixed breed dogs tend to have better temperaments and less health problems in the long run.
A great local Minneapolis dog rescue is MARS (Midwest Animal Rescue & Services).
2. Breeders are definitely a good option if you're looking to get a pure-bred dog. Again, it is very important to do your homework. You want to make sure you are getting your dog from a reputable breeder. This breeder will breed for good temperament and health. There are many "back yard" breeders out there. These people are just looking to make a quick buck. These breeders do not breed for health or temperament and do not always take very good care of their dogs. A good trick to ask a potential breeder is, "May I see the puppies with their mom?" If the breeder refuses, stay away! Look for a breeder with a good history of healthy lines of dogs.
3. Pet store are actually one of the worst places to get a new dog. Pet stores many times carry animals from Puppy Mills. These are places where again, they are just looking to make a quick buck, but on a much larger scale. Puppy Mills are places you have seen horror stores in the news about. These places definitely do not breed for health and temperament. If you get a dog from a place like this, it is HIGHLY likely you will have numerous problems down the road. You don't want to start off training a dog that's bred to already be crazy. It makes everything you do much more difficult!