Yuusuke-san is starting to practice 日本語 agian

[chryuop]

Sorry Yuusuke, you are right....we kinda got carried away

Definately the first site is a must as Kyle told you. A couple of these site have forums too so to have multiple help choices.
Tae Kim's Japanese guide to Japanese grammar
Nihongo o Narau - Pics Japan - Children's Day
日本語資源 - Nihongoresources.com
Japanese-Online.com ::: Online Japanese Language & Culture Resource Community :::
This is a kid's site written in Japanese with option to see it in English too. Not grammar source, but good to practice reading:
キッズ・ウェブ・ジャパン - Web Japan
If you need a good dictionary with examples, try this:
http://www.alc.co.jp/index.html
If you want someone to help you learn you can try this (not for free tho):
Japanese Lesson From Basics