In my frequent searches for specialized books, I often come across good ones that are completely unpromoted. Some places you swear are trying to collect their own books! The Center for Louisiana Studies has published a nice series for the Louisiana Purchase bicentennial. Volume V, Part A of that series is titled The Civil War in Louisiana: Military Activities and is an excellent 750 page collection of previously published essays and journal articles. Go here for a table of contents.
Alternatively, those readers more interested in social and political subject matter have Part B, The Civil War in Louisiana: The Home Front for their perusal. Click on this link for more information about this book, including a contents list. Both A and B are edited by noted Louisiana historian Arthur Bergeron, Jr. and would be great additions to anyone's library of Trans-Mississippi books. The Center recently published a new much appreciated edition of the long out-of-print Yankee Autumn in Acadiana and I plan on regularly monitoring their site for any upcoming reprints or new publications.