Making Sense of Japanese: What the Textbooks Don't Tell You

I don't have much to add after pm215's excellent review, only to say that I found this book more helpful when I was a solid intermediate learner, rather than anywhere in the beginner stages. By that point I knew each topic well enough to understand the fine distinctions the author was trying to make, as well as understand why I would need those fine distinctions.

A great little book, but definitely as a supplement and not as any source of knowledge you're studying for the first time.