Males are capable of producing pups at about 5 or 6 months, but AKC won't accept a litter to be registered unless the male is at least 7 months.
In my experience, they don't really have a clue what they're doing until about 15 months and some don't even act interested in a female until they are at least a year.
Here's a website with a lot of information about studing, breeding, whelping, etc.
www.debbiejensen.com