There are specific books with respect to each law. However, the question arises is how many books will you read. Therefore, I recommend you monitor this forum. You will find that a lot of discussions has happened in the past on each labour law.
Secondly, a lot of changes keep on happening. Changes happen because either government changes this or that act or some high court or the supreme court gives a verdict with respect to some labour law. All these changes are discussed on this forum.