With the due date of our first child later this week, I picked up, Now What? The Chapman Guide to Marriage after Children. It is a little book that you can easily finish in one sitting. Gary Chapman has made a career out of his theory of the five love languages, and has now added the concept of four "seasons" of marriage. I have read and found both books helpful - The Four Seasons of Marriage & The Five Love Languages - and this book was so small and so appropriate that I looked forward to hearing what Now What? had to say.
Dr. Chapman spends five chapters talking about the things which can cause strain in a marriage - discipline, finances, and schedules, as well as talking about the importance of simply making marriage a priority and what the key to maintaining or re-establishing intimacy is.
This is not a book on parenting - it is a book on marriage as parents. One of the things I read again and again is books by Christian authors as well as non-Christian authors is that the best parents are the ones who have a strong, healthy marriage - and continue to work on it. This is something that my wife and I have taken seriously, and even though we have a number of parenting books in our "to read" queue, the marriage books are the ones we want to give the most time and attention to - and not just now, but throughout the course of our marriage.
As far as Now What? goes, I would recommend reading the aforementioned Four Seasons of Marriage and The Five Love Languages. If you can find Now What? at the library, definitely check it out, but much of the material you can find in those books.
Other books relating to this topic:
When Two Become Three
Creating an Intimate Marriage
Becoming a Dad