The Civil War Sites Advisory Commission did a report in 1991 on what they considered the 384 "principal" engagements of the war, including Indian conflicts which they believed had a direct influence on Civil War operations by the diversion of funds or troops (I can't remember the exact wording, but that was basically their reasoning).
The report basically identified the state of battlefield preservation for each of the sites, as well as who owned the land, the condition of the land, which sites were most under threat from development or environmental conditions, and available preservation opportunities. Although a bit dated, the work that the Commission did was pretty thorough and informative.
I believe the map was made by a non-Commission source (Wikipedia user, maybe).