Hi Lindy, I have that book and like it very much. It is not flawless though. The best thing I can say is there is a lot of good information in there but read other sources that have other opinions and make small batches to test things. Read the whole book cover to cover before you start. Do not read say shampoos only and try to make one without reading shower gels. The 2 biggest issues you will have is having your product stay clear say below 60 deg. and not being too thin. ADD LESS WATER!!!! You can always add more later. The book says you can use oils high in palmitic and stearic acids if done so in small amounts, I say not at all. Trust me on this one.
As for the recipes in the book I have not followed one to the letter. I see what she tries to do by using different oils and use that information to make my own recipe. I don't think I have made a batch of soap yet where I followed a recipe 100%. I always go my own way.
Have fun making liquid soaps. I love it. Do handle the koh with care, it is not as nice as the other lye.
Bruce