I had never heard of "a mighty GIRL" before. Many resources for books, toys, and more. This particular page has read aloud chapter books. There is also a longer list with all different types of books, a list of historical figures, and much more.
This blog, started by two New York moms, reviews many children's books. They are searchable by title, author, reading level, and more. Their rating system is a bit different than many other (such as levels of humor) and has a broad list of categories/themes