Gravesong (The Singer of Terandria #1)

Actor, singer... necromancer? 

All the world's a stage... even when you're teleported to a new world. Struggling actress Cara O'Sullivan is walking down the streets of Galway one moment, and the next she's in an ancient tomb in a faraway world. Alone in the dark, with her cellphone as her last tenuous connection to home, Cara sings her favorite song. To her astonishment, her song casts a spell of light into the world... and from the depths, something hears her.

 

Challenged by a ghostly knight, a tragic necromancer, and hordes of undead, can a young woman who doesn't believe in heroes become one herself?