[packetpirate]

I have used a few methods, including My Japanese Coach for the Nintendo DS, the Genki book series, and Japaneseclass.jp

Honestly, I think Genki is a great start.
My Japanese Coach took a linear approach to things and it was hard to fully grasp the grammar because they presented it as though it was vocabulary and very rarely explained it in depth. They also had a few vocabulary that were blatantly wrong, as well as the wrong stroke order for a number of hiragana/katakana/kanji.

Genki almost seems as though it's something a child in Japan uses to learn the language. It's very simply to understand and they do explain things very well.

As for Japaneseclass.jp, I would have to say it's not a good way to learn the language, but it's good for reviewing vocabulary/kanji, so I think it's worth it to make an account and practice from time to time.