I recommend getting a dog from the shelter and saving its life, but if you insist on getting a purebred dog, I always thought I would like a rat terrier:
These aren't pics of my dog, but instead some I found online.
I'd definitely recommend small dogs over larger dogs though.
Dogs require a ton of commitment and time to be raised well, and I wouldn't recommend a dog to anyone unless they are prepared to devote lots of time to it. Anyone can get a dog and lock it in a kennel outside all day, but that isn't being a good owner.
Good luck.