D.W.
Hello!
When our daughter was that little, we had a lot of sleep issues, too. We referred to
"Secrets of the Baby Whisperer: How to Calm, Connect, and Communicate with Your Baby by Tracy Hogg and Melinda Blau" which seemed to us common sense advice on the issue. They also address how to stop habits that started as good intentions, but have evolved into new problems : )
I liked the tone of the book and the way she goes about things, working towards the desired result without forcing either parent or baby to tear their heart out.
Good luck!
D.