Christian Writer's Market Guide by Sally Stuart. Updated annually. Includes contact information and guidelines for publishers and periodicals.
A Writer's Reference by Diana Hacker. Submit a clean manuscript by brushing up on effective sentence structure, word usage, and punctuation.
Book Proposals that Sell by Terry Whalin. Highlight it. Mark it up, Dog-ear the pages. Make notes in the margins! You will use this book over and over and over again!
You Can Market Your Book by Carmen Leal. Takes you behind the scenes of book publishing and provides you with valuable advice to help you succeed.
Publicize Your Book by Jacqueline Deval. Helps you plan and implement a strong marketing plan to generate attention for your book.
An Introduction to Christian Writing by Ethel Herr. Just as the name says - Good overview.
The Complete Guide to Christian Writing and Speaking by Susan Titus Osborn. Another good overview.
Write His Answer by Marlene Bagnull. An encouraging Bible study specifically for Christian writers.