I tend to find that cookbooks often have a rather odd idea of ingredients (honey and agave syrup, anyone?) and that the recipes vary tremendously depending on the country the author lives in. This is fine, of course, so long as those ingredients are actually available in YOUR country.
For keto recipes, I would heartily recommend the
www.dietdoctor.com website. The recipes on there are very carefully designed on ketogenic principles, and you can choose menus that provide anywhere from less than 20g up to over 50g carbs a day, depending on your personal preferences.