Hardtack and coffee and Si klegg can also be had for free in ebook format as well. It always strikes me as ironic to read 18th century memoirs on a 21st c electronic device. I don't know why. "From the Rapidan to Richmond" and "Detailed Minutiae of Soldier Life" are good reads, too. You can get them at Gutenberg. There's also a fascinating little book called "Our Campaign Around Gettysburg" which is the story of a 90 day militia unit that marches all over southern Pa and Md on the fringes of the battle of Gettysburg. They never get involved of much of anything, but wonderful descriptions of tent camps and muddy 6 mile marches in the rain sound like the kind of things that reenactors just might actually experience in the hobby.
Pine River Boys, Co I, 7th Wisconsin
"We're... Christians, what read the Bible and foller what it says about lovin' your enemies and carin' for them what despitefully use you -- that is, after you've downed 'em good and hard."
-Si Klegg and His Pard Shorty