 It was here that he wrote most of his best songs, including an album of country songs used as the sound-track for the movie "Electra Glide in Blue".In 1969, while living in Sonoma County, California, he formed the Frontier Constabulary with Mitch Greenhill and Mayne Smith.After Spoelstra left to resume his solo career in 1970, the band continued as the Frontier.