It might be very difficult to find the grave. First, I wonder what proof your source has that William Crow is buried in Oklahoma, being that on the 1900 census, Martha is listed as a Crow, and married. Maybe they have an obit or some record that provides a clue as to what cemetery, ect. William is buried in. There were not many records kept during that time. This is some websites you might be able to get some info from. First, I would try to make sure when William died, and where, for sure.

http://www.rootsweb.ancestry.com/~okjeffer/resource.htm

http://www.sirinet.net/~lgarris/swogs/

Libraries in Jefferson County (May have records of older obits, or cemeteries.)

Gleason Memorial Library
101 E. Main
Ringling, OK 73456
Telephone: (580) 662-2925


Waurika Public Library
105 S. Meridian St.
Waurika, OK 73573
Telephone: (580) 228-3274

It looks like your Martha Boggs Crow liked her birds, no pun intended, as she was listed as Martha Buzzard on the 1940 Census in Knoxville, Knoxville Township, Marion, Iowa, living with her daughter, Cevilla Willey. Both are listed as widows. Cevella married Sylvester Willey.

This is the obit info on William C. Crow, the son of Martha and William.

http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GSln=cr...;

William Christian Crow, Sr
Birth: Sep. 21, 1878, USA
Death: Dec. 30, 1946, USA

Died of tuberculosis sanatarium at Clinton.
Survived by two daughters Mrs Ralph Burns & Mrs Raymond Herren. Two sons Cecil & Will Jr, one sister Mrs Sevilla Willis & His mother Mrs Martha Buzzard.

Burial:
Sunny Lane Cemetery, Del City, Oklahoma County, Oklahoma

This would be the marriage record for William and Martha Crow, which you can send for. It looks like Martha might have used a J in her name sometimes, or it was an I, and looked like a J.
groom's name: William Crow
bride's name: M. J. Boggs
marriage date: 18 Dec 1873
marriage place: , Cooke, Texas