The "Gun and the Gospel," by Fisher, has been reprinted and is reaily available. It much simplifies the tensions and deadly raids that took place between the Missourians and the abolitionist Kansans, or Jayhawkers as they were known, and as often happens, conflicts in marginal areas, with volunteer and irregular units not under regular Confederate or Union command, were often filled with strong elements of revenge. Atrocities abounded on both sides.

Fisher presents his version of the Raid without indicating that he was an actual eye-witness. Of course no single person could see more than the part of the raid directly affecting himself. Another witness to a small part of the action was O. W. Mcallaster, whose account is here: http://skyways.lib.ks.us/genweb/shawnee/library/KSHSvol12/lawrenceraid.txt
There are others, many in the Truman Library, assembled by the historian Connelley, and I believe searchable, here. http://library.truman.edu/manuscripts/connelley.htm