The Basics of Geographic Information Systems (Lloyd P. Queen and Charles R. Blinn, University of Minnesota)
Geographic Information Systems (U.S.G.S.)
The Geographer's Craft Glossary (Kenneth E. Foote, The Geographer's Craft Project)
GIS Glossary (Brian Klinkenberg, Dept. of Geography, University of British Columbia)
Map Projection Overview (Peter H. Dana, Dept. of Geography, University of Texas at Austin)
Map Projection Home Page (Dept. of Geography, Hunter College)
Database Concepts (Kenneth E. Foote and Donald J. Huebner, The Geographer's Craft Project, Dept. of Geography, University of Texas at Austin)
GISLinx Categorized List of GIS Sites
Metadata (Federal Geographic Data Committee)
Indiana GIS Initiative (INGISA)
Northwest Indiana On-Line GIS Users Community
Chicago Wilderness Browsable Data Catalog
NIPC's Chicago Regional Clearinghouse Cooperative (NSDI Node)
Chicago Region GIS and Data Catalog (NIPC and CAGIS joint Effort)