The following will get you started on your search of programs that provide GIS education. The majority of the departments listed are geography programs, the traditional home of GIS. Some of the departments have strong environmental programs, others have strong geostatistics influences, while others are very technical in terms of geocomputation. Read through these programs with your interests and strengths in mind.
If you know of other programs not listed leave a comment in the comments section.
Ph.D. Programs
Geography Programs from the Association of American Geographers
Listing of Geography Programs from Oklahoma State University
Selected Programs Websites
University of California-Santa Barbara
University of Wisonsin-Madison
University of California – Berkeley
OK