This link http://genforum.genealogy.com/cgi-bin/print.cgi?peak::566.html shows that Floyd Joseph Peak died in Caddo Parish in 1892. Your best bet would be to check the cemeteries near where he lived. To find that out, go to the Caddo Parish Courthouse in Shreveport and look at successions during and after 1892 under his name. Generally, these papers not only list the land but sometimes the death certificate which may give you more direction as to his burial site. If he wasn't buried on his own property or a nearby cemetery, you might consider checking the cemeteries of Kent County, Texas as two of his siblings are buried there. His father and another sibling are buried in McLennan County, Texas. He married what looks to be his first wife's sister in Lafayette, Arkansas which is another possible location.
You can also check with the cemeteries at the bootm of this link. http://www.usgwarchives.org/la/caddo/cemetery.htm