I thought some people might be interested in this contest... Tofugu is offering the Genki I and II, plus the two workbooks. It might really helpful and useful to work your grammar!
You can sign up here by answering Tofugu to the question : http://www.tofugu.com/giveaways/genki-japanese-textbook/?lucky=19848
(P.S., this is referential)
Good luck to everyone who wants to try!