My wife, LaVonne, and I have researched the KNOOP/KNOPF names throughout the Western United States for the last several years, and have presented the results of our research in these books. The books are the next best thing to visiting over 800 county courthouses and doing the on-site research yourself. You may see more detail on these books, and the areas included, by clicking http://www.baseballundertaker.com/knoop.html. I assure you that you will find some information you are missing in these books. Try them. You will not be disappointed.
Thanks for reviewing our books, and happy hunting in your genealogical pursuits!!
Bill Lee