Freelance Copyeditors

http://www.the-efa.org/res/rates.php
The Editorial Freelancers Association has a handy rate chart for ballpark figures, including copyeditors (posted 6/16/11).

http://www.edit1to1.com/
Here is the website of editor and copyeditor Carl Arnold.  Carl has edited books forvarious imprints at Penguin, HarperCollins, Random House, Holt, Simon & Schuster and Cambridge University Press, and worked as a copyeditor at the New York Times.  I've known him personally for fifteen years and can wholeheartedly recommend him.