You must really be lucky to live in Japan. Wow, I'm jealous.
I completely agree with Dreamer though. One of the best ways is to amerce yourself in the culture, listening carefully to the words and translate them individually. After a while, you'll be able to understand the sentences, but then comes the difficult part for foreigners is mastering their grammar system. You'll often find pieced together terms that are made up of multiple words that define specific conditions and descriptive meanings. It all seems cryptic to a Gaijin at first, but soon it becomes more and more clear when you recognize the pattern.
For now, I suggest cross reference translating simple terms and studying basic conversational phrases. Make use of translators every chance you get online and most of all, be creative and open minded when translating terms. Most online automatic translators can make serious mistranslations and use otherwise unusual terminology in place of a simple component of speech. Plus, you've got us! I'm more than certain people here can help tutor you now and then with the language. I myself am still learning, but I'm starting to piece things together and understand conversations through translators.
I guess living in Japan is the best way to learn Japanese. I am an English tutor from LA, I am interested in moving to Japan. Since the economy is not good, is it easy to find an English tutoring job in Japan now?