You may have already found the info you were looking for , though, I just did a google search for an Elizabeth Tillman, who lived in NY in the late 1700's. I didn't find any info on google except your query here. I read in a family book that she was the daughter of Major Christopher Tillman and married Luther Trowbridge, a cousin of my 5th great grandmother, Mary Trowbridge Snow. The family book is a biography of my 3rd gr grandfather, Erastus F. Snow, written by my great grandmother's sister, Theresa Snow Hill. It is a historical novel, based on letters and documents collected over hundreds of years. It sounds like she was a notable person, and the name sounded familiar, thus my search.
Cheers, from CA!
Lani Davis (Lila)