How should I go about learning Japanese?

I am learning several languages right now, and Japanese is one of my favorite ones! But it's also harder because it's so DIFFERENT. I reading articles on learning Japanese, and one of them said that many Japanese learners would end up not reaching the level of fluency the would like, because of the way Japanese is spoken. Is this true? Will I end up just getting frustrated? How can I achieve fluency? Please help!