I started to learn japanese as well. For this I'm using an eBook called JIP - Japanese is Possible. I think it's very good. Okay, it teaches you the plain form mainly, but it tells you all you need to know so you could understand animes. That way learning is more fun. And the grammer is explained very good. I worked through 17 of 21 lessons. I gotta say my japanese could be much better by now if I'd learn the words.. unfortunately I have to write 3 exams in less than two weeks (actually one more, but I cancelled it).
Oh, and I found a good site which explains Kanji and Kana.
http://www.kanjisite.com/
I just couldn't figure out the difference between Hiragana and Katakana, except for the writing of course, but when do you use Hiragana and when Katakana?