Matt Thomas knows how to write a song—as evidenced in over a decade of music-making with the Weigh Down, Leaves of Lothlorien, Short Pants Romance, etc.

Sometime around 2006, he found himself in between projects, wondering what to do next. The answer came as soon as he got his hands on a Mac and discovered Garage Band.

He toiled and tinkered. He wrote and recorded one song. One song led to many. He shared a few with people. The people really liked them—particularly Jason Hammel of Mat...