Civil War research

I have been trying to do some specific research about some incidents during the Civil War. Googling gives me way too many hits and I have to wade through so much other stuff. Does anyone have a good site or an author they recommend that might be of help. Specifically I am looking for the arrests of Union soldiers for spying in Louisiana.

Perhaps one of the following:

James McPherson's "Battle Cry of Freedom: The Civil War Era"
Shelby Foote's "The Civil War: A Narrative"

Or perhaps something specific to Andrew Jackson there in Louisiana (famous hero of The Battle of New Orleans, prior to his presidency), such as the following:

Arthur Schlesinger, jr's "The Age of Jackson"

Thank you Jeffrey!