I have found some helpful information at The Christian PEN. It is a site for editors and want-to-be editors. It is a wealth of information. They even offer online classes for individuals desiring a career in editing or for writers who wish to improve their editing skills.
The Christian PEN is open to any Christian* who:
- is a freelance proofreader, editor, or other writer-supporting occupation (at any level)
- is seriously planning to become a freelance proofreader/editor, or
- is investigating the freelance proofreader/editor field.