Writers Helping WritersThis site has many one-of-a-kind tools and resources for writers, editors and teachers. There are screen-specific resources, but most of the resources will assist creative writers regardless of medium. Under Tools for Writers, find guides to character arc progression, setting planning, replacing crutch words and more. Writers Helping Writers also run webinars and contain links to many other excellent writing resources.
The AFTRS Library holds a copy of The Negative Trait Thesaurus: A Writer’s Guide to Character Flaws.