If I may jump in too
Agree, Genki is a good choice. Also Minna no Nihongo. But make sure you get the one that's in Kana and not Romaji. This comes with an audio CD too so you can do the listening exercises at the end of each chapter.
Also, a great resource that I have been using for a long time now:
A Dictionary of Basic/Intermediate/Advanced Japanese Grammar
It's a good idea to get them as a complete set of 3 dictionaries so you will always have a great grammar resource at any point in your Japanese language study
The authors are Makino Seiichi and I forgot the other one, sorry
(Published by the Japan Times)