The Complete Japanese Verb Guide

Want to get a handle on how Japanese verb endings work? This is your book.The Complete Japanese Verb Guide holds your hand and shows you exactly how verbs change according to tense, politeness of register etc. Take the verb to eat, taberu. It, and more than 300 other verbs, each have an entire page devoted to showing all their conjugations, eg
tabeta - ate
tabero - eat!
taberu na - don't eat!
tabesaserareru -  was made to eat
There is also a set of handy sample sentences for each verb.
The introduction to the book gives a brief but lucid explanation of how each of the forms should be used, covers the basics of keigo and and the last chapter is a pleasant surprise - a list of 277 "suru" verbs.
The book is aimed at beginners but it makes a useful reference well into the intermediate levels. If it has a down side it would be the use of romaji, which will piss off purists, but admittedly enables absolute novices to dive straight into the passive and causative tenses and say more than "I eat...". Highly recommended for those starting out.