Gary Caplan has 2 audiobooks on Listento.it, narrated by 2 narrators. The most-rated is Sheppard's Quest.

After the mysterious death of a senator's sister in the country of Megalos, master wizard Leozanthicus is tasked with solving her heinous murder and retrieving weapons stolen from her estate. After recruiting loyal companions - including a Dawn Knight and a Mystic Knight - to join him, the group embarks on a quest to discover the truth behind the chilling attack. But their investigation only leads to more questions and takes a harrowing turn when they discover that the Chaos Warriors - an ancient enemy of more than just Megalos - are mounting a large-scale assault. As Leo closes in on the truth, more and more enemies surface as he uncovers a sinister conspiracy behind the planned invasion of the Chaos Warriors. Forging ahead with assistance from a race of star people known as the Quarran, Leo discovers shocking evidence that proves the Chaos Warrior attack is far more imminent - and far more dangerous - than previously believed. As treachery begets more treachery, Leo and his allies find themselves in a race against time to save their world against the Chaos Warriors and their evil horde. Part mystery, part fantasy, Clues of Chaos is brimming with suspense and adventure that will have you racing to the end yourself.
©2016 Gary Caplan (P)2016 Gary Caplan

Alliance fleet officer Robert Sheppard and his crew aboard the Phoenix have a sworn duty to uphold order in the universe. Even when that duty means they have to put their lives on the line, each individual is ready to make the ultimate sacrifice for the Alliance of Worlds. In his latest adventure, Sheppard may have to do just that. He is facing dangerous new enemies with advanced technology, weaponry, and intelligence. It may just be his most deadly adventure yet! When Sheppard is asked for help by his new allies, the Talcon, he can hardly refuse. From their planet-sized spaceship, the Talcon Starcity, the alien race is looking to establish colonies in the Milky Way. Their impressive technology forces most other planets and organizations to play nicely. The Talcon have a problem that they think Sheppard can solve. Animals from Starcity are going missing. It seems like such a simple mystery, but the solution to the puzzle will take Sheppard across space and into the hands of a strange new entity. Despite his many years working for the Alliance of Worlds, there is still much Sheppard doesn’t know about the universe and its many species. He’ll soon discover some hard truths!
©2018 Gary Caplan (P)2018 Gary Caplan