Army Lineage Series - A series of essays about the history of the United States Army.
Civil War Artillery (civilwarartillery.com) - An extensive web site dedicated to American Civil War artillery.
Civil War Maps Collection - Library of Congress online collection containing scans of vintage Civil War maps.
The Life of Clara Barton - A site containing information about Clara Barton, an important figure in the Civil War, and founder of the Red Cross. Thank you to Mrs. Joanne McClaine and the Creative Girls Adventure Book Club for bringing the site to my attention.
The Meade Archive - A site containing information about Major General George G. Meade, including information about The Meade Pyramid.
The Perry-Castañeda Library Map Collection - This is a University of Texas at Austin web site where I found the National Park Service maps used on this site. These maps are given out for free when you visit the battlefield and are in the public domain.
Shotgun's Home of the American Civil War - A site with a lot of detail on the American Civil War. The weapons section is particularly useful.
Trailhed Graphics - Trailhead graphics makes maps of several Civil War battlefields. They show the location of every monument on the battlefield. These maps are excellent! They are sold online and at the bookstores of several battlefield parks.
Virtual Gettysburg - This site has a photograph of every monument at Gettysburg. I found it very useful in tracking down monuments I had photographed but had forgotten to list in my notes.
Canon - I'm a long time Nikon owner, but my first foray into digital photography was with a Canon PowerShot A40 camera. Canon makes some impressive "point and shoot" digital cameras with enough features to satisfy serious amateurs.
Eastman-Kodak - Film photography may be a dying art, but Kodak still produces the best photographic film.
Nikon - I'm a very satisfied Nikon customer! When the back door of my camera broke a few years ago, Nikon sent a replacement part out quickly, and for a reasonable price.