Join an organization, such as the National Association of Independent Editors and Writers (NAIEW) or ACES: The Society for Editing, to connect with others in the field. Publishing Professionals Network (PPN) lists jobs as well as other membership organizations. You can also subscribe to Editors Only newsletter to receive a directory of professional associations for editors, as well as current job openings.
I have over 18 years of experience writing about, researching, and analyzing complex public policy, historical, political, and international affairs subjects ranging from UN peacekeeping to ancient Rome and my work is regularly published online by a variety of websites. Published in Newsweek, the Modern War Institute at West Point, Mic, The Jerusalem Post, The Jordan Times, and other publications.
It’s always sensible to follow due diligence in submitting your first draft of your book to an editor by making as fool-proof a copy as possible for you because first, it is your own creation, and secondly, a horrid draft sent your editor can end up frustrating both you and him or her. Make your own corrections to the extent you can, so that will make the job of your editor that much lighter and the end result would be a lot more effective.