Julie wrote, "Can any one help me find my great grandmother? Mary Ann Hibbs. Last known residence,was Salmon, Idaho.Lemhi,Idaho.Married to James Ruben Hibbs.Maiden name, was Mary Ann Cox ..."

Julie, what do you mean by "finding" your great-grandmother? Are you trying to find out where she is buried?

You don't provide any idea of when she was born, so it's difficult to know what resources to check. However, I did find this possible match in the ID Death Index:

Idaho Death Index, 1911-51
Name: HIBBS, MARY ANN
Year: 1939
Certificate Number: 119426
County of Death: Lemhi
City: SALMON
Date of Death: 05/29/1939
Date of Birth: 10/01/1869