This is not all it might at first appear! This is not really a source book - it doesn't actually contain any speeches or monologues - it merely tells you where you can find them! Not particularly useful for the committed actor or tutor - that kind of stuff, you are highly likely to already know!
Despite this being called a 'sourcebook,' I really don't think it is clear and obvious in the description that this book contains no actual monologues! It lists off many, including an age range for performance, which play it is from, the page number and a brief description of the monologue. However, its extremely difficult to even select one from this list... it doesn't indicate how long a monologue is. You could end up going to the trouble of ordering a play only to find out the speech is only a few lines long. My advice is to seek a book which contains many actual monologues as choosing from this book is more of a stab in the dark than anything else.