My advice is to get the book "Smartwork" (Vol 1). Probably the cheapest and quickest way to get it is to order it from Mark Jansma at
www.coonriverkennels.com
"Fun Training" (unenforced things) should start the day you bring your pup home. Enforced (disciplined) training usually begins at 4 to 5 months (depending on the dog).