David Rumsey's Map Collection - Thousands of high-resolution digital images of maps from the David Rumsey Collection, one of the largest private collections of historic maps in the US. Focus is 18th and 19th c. North and South America cartographic materials.
Infography about Map Collecting - Online and print resources recommended by a professor emeritus who specializes in research about map collecting.
International Antiquarian Mapsellers Association (IAMA) - The IAMA's main purpose is to promote the professional trade of antiquarian, collectible maps and related books combined with promoting public interest, appreciation and education with respect to antiquarian maps.
International Map Collectors Society - London-based organization for those interested in maps, including collectors, dealers, librarians, and academics. Activities overview, events calendar, journal, library, and resources.
Map the Universe - A weblog documenting one person's journey into the world of antique map collecting.