There is a lot of good information here already. I am going to add something that I think is the most important- start shopping for a breeder NOW!! Many good breeders only have a few litters per year, and if you can pick out the breeder you like best right now, it may be a year before bringing home a new baby.
Remember that good breeders will keep the pups for at least 12 weeks, so when you add that four months to time it takes for the female to be ready to breed, and then the gestation time, you may be a year out. It's just a thought.. many people research for a long time and then decide they want to pup "now." Many end up settling for what is available "now." Find a breeder, get on a waiting list, and wait, wait, wait!! Good luck