I am so glad that my answer to your bite inhibition question was useful and flattered that you came to visit my website! After reading your comment here, I realized you’d also posted this question on Yahoo Answers so I answered it there. Here is what I said…

There are really no short and easy answers to these questions and, without meeting your dog, it’s hard to even feel confident making suggestions. Aggression is SUCH a serious issue and not something that can be remedied easily.

The good news is, Kit is a PUPPY and the chances that she’s really a dangerously aggressive dog already are fairly slim! Keep in mind that I am just another Shiba owner – not a dog trainer or behaviorist – but here are some points/ideas that may help you figure out what to do next.

– Shibas are not necessarily more “dog aggressive” than other breeds, but they are a more primitive type breed. Their social structure and communication methods are very different from breeds like spaniels. They tend to have a very well-defined sense of personal space and little patience for other dogs who invade it!
– Like I said before, Kit is just a puppy. She’s just doing what puppies do, although possibly to enthusiastically. She needs to learn self-control and better communication skills.
– There probably were a handful of warning signals each time she “attacked.” Unfortunately, most new owners don’t read doggy body language and if those signals flash by in an instant, you will miss them.
– A good trainer can help you learn to read your dog, other dogs, and situations before the escalate. Find one. Preferable a member of the Association of Pet Dog Trainers (doubtful that this includes the PetSmart trainer).
– Keeping her away from other dogs is reactionary and will probably have opposite the desired effect. Socialize her with older, calmer dogs who will not get in her face and will help her learn how to communicate and negotiate with other dogs. A good trainer can help you find dogs to socialize with.
– All of this socializing and training will go more smoothly if it can be done off-leash (in a safe, securely fenced area of course). Most dogs feel much more insecure when leashed because their freedom to protect themselves – and even to communicate properly – is restricted. Also, your stress and concern are communicated to her through a tense leash, making her feel there is a problem she has to handle for you. (I’m not suggesting you go to a dog park and turn her loose with other dogs to learn to socialize. Dogs do learn from other dogs though and the right doggy teachers can make a big difference.)
– Re the HOA, I don’t know anything about that sort of stuff, but my GUESS is that they would have to have documented aggression incidents (dog bites involving hospitalization) to make any legal demands on you.

Also, here are some great books that might help you.

– Bones Would Rain from the Sky: Deepening Our Relationships With Dogs by Suzanne Clothier
– On Talking Terms With Dogs: Calming Signals by Turid Rugaas
– The Other End of the Leash by Patricia McConnell
– How Dogs Think: What the World Looks Like to Them and Why They Act the Way They Do by Stanley Coren

Pups from one-pup litters have a special hurdle to overcome. I’ve talked to a couple breeders about this in regard to bite inhibition (because of a rescue Shiba that had been a single pup actually). They told me that they try to get them mixed in and playing with pups of a similar age as soon as possible. That’s tough if you don’t have another litter available though!