This is the “Reviews” page – if you don’t have any book reviews, you can skip this page for now, or just put the reviews you have on the books page (you might want to just do that anyway). Or you could have a couple under each book and a link to “click for more reviews” leading to this page – if you have a whole bunch of them. You’ll want to style them well; if your WordPress theme has a nice blockquote style you can use it (I really love the style on this theme – which is Shiroi Hana.
Here’s an example review using the default blockquote style of this theme; but each theme is different and most don’t have blockquotes quite as awesome as this one.
There are also some WordPress plugins for testimonials you can use.