It is found in KY probate records, Fleming County, will book B, 1816-1822, pages 441-442 and those are located at image number 175 and 176.  Other names mentioned besides Nancy Payne, executrix, and James Alexander, bondsman, are William OBannon, Selverton OBannon and Humphrey Beckett, witnesses.  Pages 461-2 inventory (images 185-186) 

If you would like to upload the info to the Fleming County website, here is a transcription of the will:
(page 441 of Will Book B)
In the name of God amen I Reuben Payne of the county of Fleming and commonwealth of Kentucky considering the uncertainty of this mortal life and being of sound mind blessed be Almighty God for the same do make and publish this my last will and testament in the manner and form following that is to say I give and bequeath to my wife all my estate both real and personal during the life time of my beloved wife Nancy to make use of as she Nancy may think proper for support.  After the death of my beloved wife Nancy it is my will and desire for all the residue should there be any be equally divided amongst my children.  I nearby appoint my wife Nancy sole executrix of this my last will and testament hereby revoking all wills by me made.  In witness whereof I have hereunto set my hand and seal this fifteenth day of April in the year of our Lord one thousand eight hundred and nineteen.  Signed sealed published by the above named Reuben Payne to be his last will and testament.
Reuben Payne RP (his mark)
In presence of
Wm B. OBannon
Selv. OBannon
Humphrey Beckett

(page 442 of Will Book B)
I James Crawford deputy for Joshua Stockton clerk of the court for the county aforesaid certify that at a court held for the said county on the 2nd day of April 1821 This last will and testament of Reuben Payne deceased was produced in court proven by the oaths of Selverton OBannon + Humphrey Becket witnesses thereto subscribed + Nancy Payne the executrix named in said will qualified thereto and gave bond in due form in the penalty of five hundred dollars with James Alexander her security.  Said will was ordered to be recorded which was done. Given under my hand this date above.

Submitted by Kate Renner