Are you serious about beginning ethnic German research? The appendices include sample letters in German, society contact information, suggested websites and more. The book is worth the resources in the appendices. Personal records are cited. Neither maps nor other historical details are sourced. Where would the reader find the specific maps used as examples? On page 7, the author states that the scope of his book, "This guide covers the areas that today are part of Germany, that were part of the German Empire from 1871 to 1918, as well as Austria and Switzerland." My interpretation is that only German records between 1871 and 1918 would be discussed. My ancestors arrived in America in 1833, 1850, 1854, 1862 and 1864. The author covers many facts with tips and timelines for these earlier migration patterns. Yes, the book is worth looking into to see if it covers your research needs.
Also, James Beidler has authored Legacy Quick Guide: German Genealogy. This four page laminated guide provides a reference that includes history, maps, basic resources, timeline, research strategies, common terms. A supplementary guide to the book.
The Best of Roots and Branches collects the editor's, Terri J. Bridgewater, choice of Beidler's articles from Pennsylvania's only syndicated family history newspaper column. Topics include case studies, methodology, DNA, web sites, newspapers, records, Germans and tips. Tips and tricks for any genealogist. Written in Pennsylvania; pertinent to any area.