The Complete Writer's Guide to Heroes and Heroines

The usefulness of this book depends on using it well. I would never start character creation with this and wouldn't recommend anyone else do so, either, especially main characters. But once the character is developed, archetype is one way to explore further. It's also fun to try fitting film and literary characters into these types (best way to see that the greatest characters won't fit perfectly into any single type).

Awareness of character types is definitely useful to a writer, as long as one doesn't lean on them. And this is the best archetype book I've found.

This book was recommended to me by a writer friend and I found it to be a wonderful source for character development. It specifically identifies 16 "master archetypes," complete with thumbnail sketches and descriptions of specific qualities, flaws, background, styles, and possible occupations.