I whole hearted recommend the Genki textbook series. More info here: http://www.japannewbie.com/2009/01/06/textbooks-for-learning-and-teaching-japanese/

I recommend Yookoso and Genki textbooks. They are both great to get you from nothing to an intermediate level.

As stated the Tae Kim's guide is a great free online resource.

If you wish to mostly learn to speak and listen then the Rosetta and the Pimsleur series are good.

It probably depends on if you're trying to be self taught or have a real teacher. I think "Minna no Nihongo" are good books to get you to an intermediate level. The best reference I've seen is Tae Kim's Guide.

I've loved my Japanese in MangaLand books (by Marc Bernabe) since I first got them nearly 3 years ago... I've used them along with free internet resources like Tae Kim's Guide to Japanese.Entirely self taught for nearly 3 years now.

"A Dictionary of Basic Japanese Grammer" by Seiichi makino and Michio Tsutui and published by The Japan Times is by far the best book you will ever buy in relation to Japanese study.

I would pick up Remembering The Kanji by James Heisig. While you won't learn the pronunciation of the Kanji, you will learn how to recognize and write ~2000 kanji. Not only that, but you will have a pretty good mnemonic framework that you can use to work on the pronunciations, and you could potentially gain insight into how your memory works.

Of course, you would use it in tandem with the other books suggested.

I personally believe one should take their knowledge from a variety of sources as opposed to just one. So I will recommend a few books that I personally use a regular basis.

• Genki (as mentioned by many before me)
• Japanese Sentence Patterns for Effective Communication: A Self-Study Course and Reference
• The Handbook of Japanese Adjectives and Adverbs
• The Handbook of Japanese Verbs
• Japanese the Manga Way: An Illustrated Guide to Grammar and Structure
• Crazy for Kanji: A Student's Guide to the Wonderful World of Japanese Characters

Good luck!