Monster Shark    by Stephen D. Sullivan
Price: $1.99 USD. 15720 words. Published on September 25, 2010. .
... The megalodon came at her from below, jaws gaping. Though it could swallow her whole, Umira doubted the beast would do her that favor.... "Monster Shark" is a thrilling undersea sword & sorcery adventure packed with magic, monsters, grisly deaths, and -- of course -- ravening sharks. It features Umira the Accursed from The Tournament of Death, Stephen D. Sullivan's free online novel.

Captain Nemo Vs. Megalodon    by Flash Rex
Price: $2.99 USD. 14900 words. Published on November 13, 2012. .
Before 20,000 Leagues Under the Sea, the infamous Captain Nemo faced his most dangerous and unique foe: a huge shark thought to be extinct-Megalodon! Ian Crane, a young secret agent is sent by a desperate President Lincoln to find the reclusive Captain Nemo and deliver a message that may turn the tide of the Civil War. Crane finds himself between Captain Nemo's famous Nautilus, and a giant shark!