Seems like every week or so someone posts a question like this to which I respond, read David Evans, Sherman's Horsemen: Union Cavalry Operations in the Atlanta Campaign. Despite the title, we are not likely to find a better study of Confederate cavalry in our lifetimes. If you want to know what the Kentucky brigade did during the July-August period, find a copy.
For history and preservation of Brown's Mill, the most important of Wheeler's battlefields, try here --