TBH, I think it would be pretty easy to write a parenting book, especially after having one or more children.
It's just common sense really, once someone has explained to you the reasoning behind what may seem like crazy methods, it's totally understandable.
Even now with DS and DD I say things to DP about dealing with them that he thinks are mad, but once I explain why, and explain what it is that's really happening, it falls into place.
I can practically guarantee to all those first-time mums, you will work out what to do without tons of expensive books, you will be able to get baby into a routine and en joy it and have fun, just as much as you will get tired and tearful and aggravated
The best thing to do, IMO, is to just chill, let it flow, which it will do, and remember, it really isn't worth getting that stressed about, and you'll be fine.