See this FAQ.
You will need an EIN from the IRS, which you can get over the phone in about ten minutes. You will also need to prove to Apple that, if you publish as a company, you are a legitimate company. Doing this is easy: you just scan the relevant documents and send them to Apple. (You will get instructions on how to do this.)
You will not be able to publish anything in the HK bookstore though. Currently 32 stores are available, basically US, Canada, Australia, and most of Europe.