Get yourself a copy of the Official Military Atlas of the Civil War. There was a reprint put out by Barnes and Noble within the last several years. Amazon.com has used copies for around $20. These aren't the best reprints but they'll work - this is the digger's bible. There will be more maps of battles and camps than you will have several lifetimes to chase - most major battle sites are Fed property, many camps under asphalt and concrete but there's still places on private property if you research and get permission plus be in a CW area.