The site doesn't cover grammar. If you haven't heard of Tae Kim's guide, you should definitely check it out since it's completely free and covers enough to get you started:
http://www.guidetojapanese.org/learn/
If you're more of a textbook learner and have it in your budget, here's a quick comparison table of popular Japanese textbooks (I can personally vouch for the Japan Times' series of books since that's what I went with):
http://rtkwiki.koohii.com/wiki/Comparison_of_Japanese_Textbooks_Table