Once you have researched the breed of dog that is going to be most suitable for your family, contact the breed club of the breed.
The club secretaries are the ones with the knowledge of the breeders, what their litters are like, when they will be breeding etc etc.
Expect a good old interview on the phone by them, they need to know who to put you in touch with
When I got my last cocker, way back in the 00's, I spent ages with the club secretary chatting about my experience with cockers, what I was wanting from a dog - did I want show type or working, what our lifestyle was like, would I be interested in agility/showing/working , was I fussed on the colour etc etc, before she put my name forward to a reputable breeder who was going to be breeding that year. Then again, a long phone call with the breeder, then invited to the home to meet the dogs - to be told I was on the reserve list. I never got to pick my dog, she picked the dogs to suit the owners. Alfie was a wee monster ( as cockers can be, but she knew I had experience and wouldn't be ringing up saying take him back I cant cope, because I had been there before - always had cockers )
He wasnt cheap
Good breeders only breed to improve the gene pool.They do a lot of research and spend a lot of money in doing so to ensure there are no defects being passed on down the generations so they breed rarely and their litters are expensive and they have waiting lists. But they are also the breeders who will take a pup/dog back if circumstances change and will be there for you when you are struggling getting through the biting/chewing stage
Right now we have a frenchie/Pug cross, came from an unplanned litter from a friends bitch and was a freebie. So different from a cocker, adorable, a snuggle monster, excellent with children other dogs, everyone, but still at three years old can not go through the night :( When I researched them I was reading this and I was saying thats mad, all my cockers were clean by 10 weeks, any dog can be trained to be clean and I got laughed at. I now eat my words.
FB has a page for all breeds and its worth joining a few to get a feel for the breed from real owners