I was able to find a plat of land and owners' names of Elk City during the 1870's. It would be worth your checking with the library about your family. I found the record with help of geneaology volunteers on duty in that section at the Independence Public Library in Oct 07. It took some digging through old papers on a bottom shelf, but I was able to get a copy of what showed my great-great grandfather's land along the river south of Elk City.

His name was Joseph Worley Elliott (Sr.) from Shelby Co, IN, who came to the Elk City area and got land in 1873, along with several of his grown sons, my great-grandfather James A. Elliott among them. Unfortunately, the land was lost in payment for court costs in 1878-79 when Joseph was found guilty of manslaughter in a shooting in nearby Indian Territory (IT). In researching Joseph's case, I have learned that the federal district court, presided over by Judge Isaac Parker, of what was then Western Arkansas had jurisdiction over crimes committed in I.T.