“Who Were You Thinkin’ Of?” was recorded in 1979 by by Jim Glaser, one of three authors of the song. Another co-writer is the author Cathie Pelletier who has written excellent novels. I know it best from the cover by Wilco which was originally on a European CD single. The Texas Tornados also covered it; their version is probably the most popular and influential. Check out Flaco Jimenez on accordion.