Go to PetSmart and buy some of the feeder ones or go to a bait shop and get some. The bait shop will have healthier, full-blood fatheads, where as PetSmart will have emaciated, possibly hybridized Pimephales sp. Or you could order some pure-breds from online. Give them a 10 gallon tank with a propped up flat stone that is about 2-3" off the floor to where it makes a cave. No substrate is needed. Just a filter, aerator, and a flat stone. Keep it at room temp and raise them on frozen foods for best quality breeders. They should mature in under six months if you get juveniles. Males will develop fat-heads(hence the name) and darker, deeper bodies. Females will fatten up with eggs. The male will care for the eggs, so just remove the females for more young. After the eggs hatch in about 5 days, take the male out. You can feed them commercial fry food, BBS, or frozen glassworms. Any questions?
The red clay pots are terracota. Nice and cheap. When you move one with eggs into a hatchery you can put another in the same place. Eventually, in a 20 long you will want to only have 2-3 breeding males.