There's a great book available, called something like "How to write children's books" or something along those lines. A new edition is published every year, and includes names, contacts and addresses of publishers, as well as the types of books in which each publisher is interested. They also give helpful tips and lots of other good info. One thing that sticks out in my memory from browsing the edition from two years ago is the following:
Most publishers prefer to find their own illustrators unless the author themselves is an illustrator. (Or, in my case, my mother is considering illustrating my books, and they would most likely make special allowances for a mother/daughter team.) They suggest you submit a book without illustrations, so the publishers, who have "favorite" illustrators, can get an idea of who they'd like to have illustrate it without having a preconceived notion.