I just read his dad's Gettysburg book, "The Killer Angels"...I gather that book was a large part of the inspiration behind Ken Burns' Civil War series. Michael Shaara also wrote a very powerful book about WWI called "To the Last Man". I'm curious to see how his son's books stack up.
An aside, Winston Groom (author of "Forrest Gump" and a pretty solid historian) wrote a book about Shiloh a year or so ago (150th anniversary of the battle)...nonfiction that reads like a novel.
Just finished the new Jeff Shaara book, A Blaze of Glory, about the battle of Shiloh. The first of a planned trilogy. Really enjoyed it. edit-just
found out it's the 1st of a planned 4 book series on the Western Theater of the Civil War.