Showing Tears of the Moon by Nora Roberts

A talented songwriter, Shawn Gallagher spends his days lost in reverie and wonder, oblivious to the wiles of women and the ways of the world. He claims that he's content with his life, but his music tells a different story - one of loneliness and desperate longing. No one understands why Shawn doesn't put his musical gift to profitable use - least of all Brenna O'Toole, a fiercely independent tomboy who has been secretly in love with him for years. But it is only when Shawn gives into the mysteries of magic that he gets the chance to fulfill his destiny as a man and a musician.