Don't know of any biography in book form.
There is a video called the "Captain Jeppesen Story" that you might find.
He gave some rather lengthy information to the authors of the IFR Refresher book, "Charts and Plates".
He was interveiwed by IFR magazine editor Paul Bertorelli in March 1992 - ok, I'm a fan.
He has a display at the new DIA terminal dedicated to him and the Seattle Museum of Flight has a section including the fabled "little black book".