Songs formulas are typically centered around the vocal, with acoustic picking underneath, and in the background an electric guitar that works as the real mood setter. The electric (typically played with a slide) can make things down and dirty with a straight blues slide riff, or simply add melancholy ambiance with a distant steel guitar sound, such as in the track "Harmony".
Harber's vocal is a very Roots Folk Americana vocal, not too twangy, but still of a deeper timbre with a throaty southern inflection.
Songs like "Small Town Murder" are dark rootsy pieces, which feature acoustic slide lines that texture everything in a hauntingly twisted country vibe, a great exemplification of this would be when the choruses of "Amazing Grace" are mixed in.
"Be Free" by Hannah Harber is available at her Bandcamp page.