In this guide, I list the steps necessary to register a free account on the Sony Japan PlayStation Network.

The Steps

1. Create a new account for your PS3. Scroll to the leftmost menu ("Users") and choose "Create New User" from the menu.
2. Enter your desired user name. This is the name that will appear in the user menu, not your PSN handle (for online gaming). Adding "Japan" to the name might help you remembe that it is your Japanese account. ;)
3. After you have finished, log in as the new user and choose "Sign up for the PlayStation Network" from the "PlayStation Network" menu.
4. Choose "Create a New Account." You cannot use another country's account to access the Japan store.
5. You will be prompted to choose a country. Select Japan. Japanese is the only language option. Enter your birthday and proceed to the next screen. Quick translation: 次へ (Next)／戻る (Back)／キャンセル (Cancel)
6. Next you will be prompted to accept the store agreement. Quick translation: 同意する (Accept)／同意しない (Refuse)
7. In サインインID (sign in ID), enter your e-mail address. This cannot be a cell phone address, and it must not already be registered with another PlayStation Network account. When you enter the address, a little window will pop up asking you to make sure your e-mail is correct, since if you enter the wrong e-mail you will not be able to receive e-mail from Sony (including important things like resetting your password, etc.).
   
   Next enter your パスワード (password) and then again to confirm your password. The password must be at least six characters and include at least one letter and one number. The checkbox is to save your password so that you don't have to type it in to login in the future. Last is your secret question and answer.
8. Next enter your オンライン ID. This is your handle for playing online games, and must be unique (it must not match any existing PSN id from any country).
9. Now enter your 姓 (last name), 名 (first name), and 性別 (gender). Gender is optional.
10. Now you must enter a Japanese address. If you don't have a Japanese address, you can use the address of a Japanese hotel or business. The 郵便番号 (postal code) and 都道府県 (prefecture) must match. Do not enter a hyphen for the postal code. If your postal code and prefecture match, the rest can be nonsense.
11. The next screen asks if you would like to receive promotional e-mails from Sony.
12. Finally, you will be asked to confirm all of the details. Click the relevant 編集 (edit) button if you made a mistake. When you are finished, choose 確定 (confirm) and you're finished.
13. Enjoy shopping on the Japanese PSN Store and playing free demos from Japan!