There is an extensive collection of data communications and telecommunications images. I've taken many of these photos myself and Steve Shepard has allowed me to use many of his too. (Thanks, Steve!) These images should help you visualize the equipment and hardware that is discussed in textbooks. Each page has thumbnail images. You can see larger copies by clicking on the thumbnail.
Wireless infrastructure (cellular, fixed, satellite, etc.)
Verizon: World Trade Center (This is a collection of photos of the remarkable communications repair job that the Verizon crew did at the World Trade Center site. It's a great example of the old Bell System "Spirit of Service")
Telco history (Images from the early days of telephony)
New England Museum of Telphony (This is a very nice seasonal museum in Ellsworth, Maine. They have a lot of working electromechanical switches.)
Newfoundland (We traveled for about 6 weeks in Newfoundland and discovered many examples of telecommunications history. One of the best is the Heart's Content cable landing. This is the location where the first succesful Atlantic telegraphic cable came ashore in 1865. There's a great museum on the site and well worth a visit.)
Voice over Internet Protocol (VoIP) This page started out as images only and ended up as a bit of a tutorial too.