NOTE: This serial takes place out of order chronologically with the Challenger Storm novels, which are being written with a definite timeline in mind. "The Valley of Fear" happens after at least book 5 or 6, but this shouldn't hinder the reading experience. I'm flying by the seat of my pants here, so I make no guarantees in regards to quality or coherence.
A second Challenger Storm novel, The Curse of Poseidon, has been announced for 2013 release.
You can read The Valley of Fear at http://challengerstorm.blogspot.com/
Challenger Storm: The Isle of Blood is still available from Airship 27 Productions.