A few questions for you experts:
1. At what age should I start bathing my puppy? (the breeder will have bathed him before he comes home at 9 weeks)
2. What product do I use for bathing?
3. Can I dry him in a towel or is he at 9 weeks not too young for a cool soft blow dry with my own hairdryer?
4. How often should I bathe him?
5. At what age is a groomer appropriate for bathing et. al.?
1. You can bathe him whenever he needs it! As you said, he has already had (at least) one bath at the breeder's.
2. Any good quality no-tears shampoo and conditioner is fine. I use BioGroom products, but other people have other favorites, and some just use human baby shampoo.
3. You don't want him to get chilled, and you won't be able to get him completely dry with a towel. So unless you live somewhere where it's REALLY warm, you probably want to dry him with a dryer. Just make sure it has variable speeds and a low heat setting. Keep your hand between the dryer and the pup, so you can tell if it's getting too warm.
4. You can bathe him as often as he needs and you want. Since Kodi is mostly white, he has been bathed every week-10 days pretty consistently since I got him. Other people with darker dogs bathe less frequently. Frequent bathing while he is young will get him used to it, so it won't be a big deal later.
5. He can go to the groomer after he has had all his puppy shots. Many groomers will also require that you give him Bordatella (kennel cough) vaccine. That said, few Hav owners take their dogs to the groomer for bathing... it's just not that hard a job. If you are planning on keeping him in a puppy cut, you may want to use a groomer for that. I take Kodi to a groomer every 3 weeks, just to have his nails clipped and his feet and "sanitary" areas trimmed. But I always bathe him myself.