A Great Site
I'm a big fan of Shelby Foote's three volume work The Civil War. It is a brilliantly researched work, elegantly written.
Now, however, there is an online site that will walk you through the major battles using animation. There is also a sound narration, but, after the first time, I turned it off in order to absorb the visuals without distraction.
Give it a look. Civil War Animated