"A History of the Eighth Regiment of New Hampshire Volunteers," by John M. Stanyan, is a regimental history. The unit participated in the action at Yellow Bayou on May 18, 1864 (also known in various accounts as Old Oaks and Bayou des Glaises), and the book has a small amount of detail on the actions of May 18. James K. Ewer's "The Third Massachusetts Cavalry in the War for the Union" is another regimental history of a cavalry unit that participated at Yellow Bayou, but there is very little detail on the battle in that one. Both books are out in reprint, so they should be available through Interlibrary Loan.