The Library of Congress - Maps Since 1960
A nice collection of maps for individual countries and regions.

Florida State University College of Law - International Boundary Study (State Department Maps)
Contains State Department International Boundary Studies. Excellent text and map files for various disputed 20th century international boundaries.

University of Syracuse Map Collection
An extensive collection of maps and links.

The United Nations Cartographic Section
The U.N. cartographic section map collections.

Map Data From ESRI
Data sets that can be used with the mapping software ArcView, which is produced by ESRI.

Datasets to Use With Versamap Software

The CIA World Factbook
Contains links to individual country and regional maps.

The Map History Site's Links to Collections
A lot of links to map collections or potentially useful map sites.