This article is from the Pinball FAQ, by Andy Oakland sao@REMOVETOREPLY.mit.edu with numerous contributions by others.
Alive and flipping:
Sega Pinball Inc. (Includes Data East)
1990 Janice Avenue
Melrose Park, IL 60160
toll free: 800-KICKERS
URL: " http://www.sega.com/central/history/history.html "
Williams Electronic Games Inc. (Includes Bally and Midway)
3401 North California Avenue
Chicago, IL 60618
URL: " http://www.pinball.wms.com "
Now sadly out of business:
Premier Technology (Includes Gottlieb and Mylstar)
759 Industrial Drive
Bensenville, IL 60106
toll free 800-444-0761
3311 N. Kennicott
Arlington Hts, IL 60004
URL: " http://capcom.ms.wwa.com/ "