It's not free, but you could always get Bob Norton's "Ultimate Country Fake Disk", based on the "Ultimate Country Fake Book 5th Edition" published by Hal Leonard Corporation. The files are just accompaniment (SGU files, no melody), but used along with the actual fake book, you can provide the melody.
Norton's Ultimate Country Fake DiskThe Norton fake disk is $48.95 and you can get the bound fake book at Amazon.com for $35.83.
I will mention that many of the songs (not all) use Norton Styles, so if you don't have them, you'll have to substitute PGMusic provided styles. Nevertheless, he has done all the chord progression input for you, which is the bulk of the work.