ArchiveGrid – Historical Archives from Throughout the World
http://www.archivegrid.org/web/index.jsp

ArchiveGrid is an important destination for searching through historical documents, personal papers, and family histories held in archives around the world. Thousands of libraries, museums, and archives have contributed nearly a million collection descriptions to ArchiveGrid. Researchers searching ArchiveGrid can learn about the many items in each of these collections, contact archives to arrange a visit to examine materials, and order copies. This has been added to the tools section of Research Resources Subject Tracer™ Information Blog. This will be added to Academic and Scholar Search Engines and Sources white paper.