Brian, one thing that I discovered using the CD version of the O.R. is that to find everything about a particular unit you need to search for the "2nd Arkansas Cavalry", "Second Arkansas Cavalry", "2nd Regiment Arkansas Cavalry", etc., and also search the colonel's name, using several parameters (last name, initials and last name, first name and last name), etc.

Every time I do a search using a different set of parameters, I find additional information. And like you said, how will I know that I've found everything?