Over 14 years of motherhood I've heard and read a lot of advice about babies. It can get confusing sorting through all of the opinions, for sure. Sleeping Through the Night... How Infants, Toddlers, and Their Parents Can Get A Good Night's Sleep by Jodi A. Mindell, Ph.D. has been one of the most valuable finds I've come across in my search for good information. The author explains the science behind sleep patterns and habits. She goes through the different stages and ages of a baby and toddler, which gives an idea of what to expect from the varying times in your baby's first few years.
I didn't find this book until just before having baby #4, and I wished that it had been around before baby #1. I sure could have used it back then. I skimmed it again before having my last baby and just pulled it back out a few weeks ago to reread the sections pertinent to Tessa's present needs.
The tips and advice in this book are invaluable! If you don't like structure and routine, this book is probably not for you. But if you want to be sure that your baby is resting completely and securely; and you want to feel less like a zombie, then this book is a great source to go through. I highly recommend it.