Edited by Mary Bray Wheeler. This lists the titles of state and local historical societies, museums, history departments of universities and colleges, etc. The addresses, phone numbers, and names of directors or department heads are given. This book is a gold mine of information. Everton's Genealogical Helper , a bi-monthly magazine that has been published since 1947.
Many libraries are regular subscribers.
This has listings for local historical and genealogical societies. Many ads for book are given, and there is a also a book review section. Professional genealogical researchers advertise in this, and it is a good way to contact people who will do research in the various branches of the National Archives, state libraries, local county records, overseas locations, etc. There is an excellent index that is broken down by surname and by geographical location. This also contains a lot of material on computer software for genealogical research.