The Lost City by Amanda Hocking

Ulla Tulin was abandoned in an isolated Kanin town as a baby. Taken in by strangers and raised hidden away like many half-blood trolls, she has never stopped searching for her parents, or wondering about them.

When Ulla hears of a project to help half-blood trolls, in the beautiful city of Merellä, she seizes the chance to discover her true heritage. She enlists the help of Pan Soriano, who is both handsome and resourceful - a half-human with telekinesis powers. And she must also contend with Eliana, a mysterious girl who claims she's being pursued. Though Ulla suspects there's rather more to the story.

Ulla and Pan work to unravel the truth about themselves and Eliana. But in the process, they realize that someone - or something - is determined to stop them. And they face a force that will do anything to keep certain secrets.

Book by author Amanda Hocking.