We've had Cruiser a week tomorrow. He's eating good now and playing a lot. He's much better. He's doing good with the potty training for the most part. He sleeps good at night. Now on to things we haven't started:
How often should I give him a bath? He had one last Thursday at the breeder's. I have brushed in almost everyday but I have given him a bath.
I bathe my yorkie once a week (every Saturday).
How often do his ears need to be cleaned?
I clean her ear after bathing so that's once a week too. As they mentioned pluck the hairs inside so that you can clean it better and it would deter any infections as mites loves dirty yorkie ears.
When should I start brushing his teeth? Do you do it everyday?
Yes start early but I brush my yorkie's teeth 3x a week only because of my busy sched.
When can he start walking on a leash? We haven't attempted to put the harness on him yet.
As early as possible, let him feel the harness as early as possible.
What age is a good age to take him to puppy kindergarten? Is Petsmart or Petco okay for this?
No idea, there is no pet kindergarden here in the Philippines. 
With all the problems with had with the vaccines and the emergency vet, etc., I am thinking of switching vets already. Is Banfield (attached to Petsmart) okay? They have a good plan cost wise.
No idea too, I'm a different country hehehehe.
I am leary about giving him the heartworm tablet that the vet gave us because the reaction he had to the vaccines. Also, he has to go on a medicine because his stool sample came back positive for giardi (spelling?). She said it's a powder to mix with the food and we should start it next week. Should I wait to give him the heartworm tablet the following week? The breeder suggested only giving him half the tablet. What do you think?
I buy the heartworm tablet for medium sized dog and cut it in half. Half of it every month.
How harmful would bird seed be to him? I posted before that we have pet cockatiels. They are messy and there's always a little seed on the floor. Well, being the little cruiser he is, he is always cruising around and trying to eat the seed. I stop him, of course, but I'm sure he's already eaten a couple of seeds. We will do a better job of sweeping and vacuuming, but we're never going to get it all. Hopefully it's not too terrible for him if he ingests a few seeds.
Seeds sometimes contains cyanide. Small amout of it is fatal for a small dog like yorkies.
What do you do about cords? He keeps trying to chew the cords to the lamps in the living room. There is no light fixture in the ceiling so we have to have the lamps. I keep distracting him from them but he gravitates back there.
This is bad, you need to train him. Say something like a firm "NO" or "BAD" so he will know that he is doing something wrong. Be consistent. Ask your other housemate to do the same when they see him chewing something he shouldn't chew.
I guess that's enough for now! I really appreciate everyone's helpful comments.
No problem, everyone will be glad to help.