Here's a small list to get you started. These are some of the titles I've found helpful in honing my craft.
In no particular order:
1. Word Painting by Rebecca McClanahan 2. You Can Write Children's Books (second edition) by Tracey E. Dils 3. The Writer's Little Helper by James V. Smith Jr. 4.Creating Characters Kids Will Love by Elaine Marie Alphin 5. Writing The Breakthrough Novel by Donald Maass 6. The First Five Pages by Noah Lukeman 7. The Writer's Guide to Crafting Stories For Children by Nancy Lamb 8. Stein on Writing by Sol Stein 9. Elements of Fiction Writing (series) by Ansen Dibell 10. Beginnings, Middles & Ends by Nancy Kress 11. The Marshall Plan for Novel Writing by Evan Marshall