Applying for a Z work visa while traveling and in China

I was wondering, I am from America and if I was traveling around Asia and decide to get a tourist L from Hong Kong and go into China. Am I able to apply for a Z work when I am in China, I would be applying for a teaching English job, or would I have to apply for it while in Hong Kong? I heard from some people that I MUST be in America...but I also have heard differing accounts of people getting a Z work while in Hong Kong.

I am really keen on traveling first but I am worried that I would have to get a return flight back to America and then immediately go back to China, the length of time and money is not favorable to me. I also want to add that I have family in Hong Kong, would that make any difference as opposed to me living in a hotel while applying for it. Thanks, hopefully it isn't too confusing.

Johnny