15th Indiana letters, photos, anything related to this famed Civil War regiment sought

If you or anyone you know has anything related to the 15th Indiana Regiment, an American Civil War unit, please let me know. Some friends and I are writing a history of the regiment. Therefore, we'd certainly like to see anything anyone has.
The 15th's is a fascinating, terrible story. It fought two major battles, the Battle of Stone River on the last day of 1862 and the first couple of days of 1863 and then the Battle of Missionary Ridge. In each battle, it lost half its soldiers, killed or wounded. Oh, how terrible. After the last battle there were so few soldiers left that those who were were put in the 17th Indiana Regiment for the remainder of the war.
My friends and I have found some awfully good stories related to the regiment: like the horror one soldier remembers of seeing and burying thousands of soldiers killed at the Battle of Shiloh. Oh, if everyone who decided to wage war could read his description first--there were be far, far fewer wars.
Then there is the story of the 15th's Chaplain Whitehead who ministered to the wounded left behind when the regiment retreated from the advancing Rebel forces. The Chaplain told his commander he could not leave those men on the filed. So, under fire, he went to several of his own men and then even some wounded Rebel soldiers to comfort them in their last moments on this earth.
Good stories all, as good history is all good stories.