June Ancestor: Elizabeth (Smith) Patterson

It's getting close to the end of June, so thought I better start on my or rather my husband's ancestor.
Elizabeth (Smith) Patterson was born in Illinois (not sure what town or county, probably Lincoln in Logan county) on April 7, 1863 to John W. Smith and Allie (Keisner) Smith.
I next find her in the 1880 census with her parents and younger siblings living in Lincoln, Logan county, Illinois at the age of 17.
She marries William Lincoln Patterson about 1881, probably in Logan county, Illinois. I have not been able to find them in the Illinois marriage index that is online.
William and Elizabeth become the parents of 5 children: Margaret Pearl (1882), Charles William (1885), Martha O. (1887), Hazel F. (1893) and Lester H. (1901), although I believe the 1900 census implies Elizabeth had 2 more children who weren't alive in 1900. The 1910 agrees, as it says she had 7 children, with 5 alive.
So the 1900 census has the William Patterson family living in McDonough County, Illinois. From then they must have moved some time in there, as 1910 has them living in Dallas Ward 1 Township, Henderson County, Illinois. This family was quite mobile, as by 1920 William, Elizabeth and Lester, along with 3 of their grandchildren (Martha's boys) were living in Tulsa, Oklahoma. In June 1928, William L. Patterson passes away in Tulsa, Oklahoma. I cannot find Elizabeth in the 1930 census. By 1940, the census finds her living with a daughter, Margaret in Hildalgo county, Texas where according to that census, they had been since 1935.
Elizabeth (Smith) Patterson passes away September 11, 1941 in Tulsa, Tulsa county, Oklahoma at the age of 78. I do have a copy of her death certificate from the state of Oklahoma. She is then buried a couple days later on September 13, 1941 by her husband at the Rose Hill Memorial Park Cemetery, in Tulsa Oklahoma.
Thanks to a Findagrave volunteer I am able to see her gravestone photo:

http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GSln=Patterson&GSfn=Elizabeth&GSbyrel=all&GSdyrel=all&GSst=38&GScntry=4&GSob=n&GRid=44694532&df=all&

I am working on tracing more back on her line, but Smiths and Pattersons aren't the easiest names to trace.
So in summary, I found her in those censuses, plus I have a gravestone photo, and death certificate. I would really like to find a marriage record for them. Otherwise I think I've done fairly well.
This is my husband's great-great-grandmother. May she rest in peace.