[SamuraiAlchemistNinja]

Here are a few more useful sites to consider:

The JLPT Study Page
Learning Kanji - JLPT

And also, I have read some very useful books that I think everyone should read:

"Making Sense of Japanese: What the Textbooks Don't Tell You" by Jay Rubin
~And~
"Basic Connections: Making Your Japanese Flow" by Kakuko Shoji.
These books are great helps and you can read them over and over again and still learn something new each time.