A few places to look for information--some of these cover older technology:

Annals of the History of Computing
www.computer.org/annals
Online version of journal; some articles freely accessible, others require subscription; searchable archives.

IEEE History Center
www.ieee.org/organizatio...sources.html
Historical articles and searchable oral history interviews on computing and electrical engineering.

Charles Babbage Institute
www.cbi.umn.edu
Has some exhibits online and oral histories of many Internet pioneers. Mostly modern, but some info about 19th century namesake Charles Babbage. Their physical archive is at the University of Minnesota.

Computer History Museum
www.computerhistory.org
Has some online exhibits starting WWII. Their site in Mountain View, CA has an incredible collection of artifacts.

Virtual Museum of Computing
vmoc.museophile.com
Mostly an extensive collection of links. A bit chaotic,but lots of information from reliable sites.

Enjoy!