From the William B. Bogardus Collection, BREWER pages from Index to Kentucky Wills to 1851: Testators, compiled by Ronald V. Jackson, Gary R. Teeples and David Schaefermeyer (1977) is now online.
BREWER in Index to Kentucky Wills to 1851
There are no BROWERs in this index. All are recorded with the surname BREWER. We do know that the two from Mercer County, Abraham and Daniel, are descendants of Adam Brouwer. As easterners of Dutch ancestry migrated to the Ohio River Valley area in the years after the Revolution, we do find a tendency towards an "Americanization" of surnames. Those descended from Adam Brouwer of Gowanus and Jan Brouwer of Flatlands, who moved west of, say, central Pennsylvania, are more likely to be found with the surname, BREWER, rather than BROWER.
In addition to descendants of Adam Brouwer and Jan Brouwer, the Ohio River Valley received migrants descended from German Pennsylvania families named BROWER (BRUER), from southern families named BREWER and from New England BREWER families. Finding a BREWER ancestor in Kentucky in the early 1800s does not guarantee he was a descendants of one of the New Netherland Brouwers. Finding documentation suitable for proving a connection from an ancestor in Kentucky back to the families of New Netherland can be very difficult and frustrating. More often then not, the evidence simply does not exist. In such cases, DNA testing if direct male BREWER descendants may be the only way to determine, or narrow down, a researcher's correct ancestry. See the Brewer DNA Project.
Family Search has made available an un-indexed (browse only) database of Kentucky Probate records. These are images of documents. I believe it is not yet complete and would expect more to be added in the future. Kentucky Probate Records, 1792-1977.