I've travelled to Japan quite a few times to visit my wife's family. Trust me, if you are planning on moving to Japan, for whatever reason, you will need some Japanese language ability to get by in daily life, even in the large cities such as Tokyo and Osaka. The attached link is to a really basic, beginning Japanese study guide which helped me out in my first year of study:
It's REALLY basic and doesn't work in all gramattical "situations", but it'll get you started and understood, for the most part. The worst part is that it's not written in Japanese. See, you'll also have to begin learning written Japanese as well. Start with the "kana" writing system, do not jump into "kanji".