A lot of people recommend Tae Kim's Japanese grammar guide. www.guidetojapanese.org/kanji.html

You can learn Japanese Online for free.. Lessons - Forums - Beginners - Kanji thejapanesepage.com/

For kanji you could try kanjiabc (http://kanjiabc.de/, can't access it right now though for some reason) and anki (http://www.ichi2.net/anki/) for reviewing. Learning what the different parts of the kanji mean (or creating own definitions for them) will help a lot for learning new kanji. I don't really study grammar so I don't know, I just expose myself to the language and learn grammar through it instead of vice versa. If you notice a pattern when watching/reading something and you don't know what it means you could look it up on http://www.guidetojapanese.org/ or just google it. I guess studying kanji is essential but I think studying grammar is pretty boring so I'll rather do something else and learn new stuff anyway. :P

For kanji, I'd recommend this: http://www.asahi-net.or.jp/~ik2r-myr/kanji/kanji1a.htm Though I believe there must be lots of similar tools/sites nowadays.