Multi-lingual keyboard support?

[dave2001]

I'm sorry if this is in the wrong spot, but it seemed the most likely place for a good answer.

I am currently learning Japanese. My native language is English, and would like my operating system to remain in English.

I would like to be able to switch between Japanese and English keyboard input quickly. I tried using preferences>keyboard>layouts and adding the different japanese options there. However it gave me no real useful changes. The only option that actually changed the output of keystrokes was the "japan kana" option, however, it only provides half of the kana. I am typing with the japanese layout selected right now in fact. Do i need to install some extra packages?

I am doing something wrong? I've used the japanese ime in windows before with much success, and I'm really hoping to get this working on Ubuntu so that I have one less thing which windows is needed for.

Help much appreciated.