I'll give another nod to Pimsleur. I took Japanese in college, but I Pimsleur for Mandarin and they were great, but I didn't go past the first set. I think they will be great for learning to speak the words, but you may need a book to learn grammar, different kinds of adjectives, verb conjugation, writing, etc. I wouldn't recommend the Rosetta Stone series that's advertised in some magazines and late night TV. It claims to teach you naturally, but it has you saying things when you don't really know what you're saying. I didn't like it at all.
The good thing about Japanese, compared to Chinese, is Japanese has a basic set of characters for writing, like letters, so you don't have to learn kanji right from the start, but it can make you lazy to learn Kanji. Also Japanese isn't tonal, so the way you pronounce a sound doesn't change its meaning.
That being said, if you really want to learn a language that can hold value in the future, learn Mandarin. There are over a billion Chinese and their economy is growing like crazy! But if you're just particularly interested in Japanese and just want to learn for fun, it's a great and fun language to study.