My So-called Haunting by Tamsyn Murray
What's known chez womagwriter as a 'buddy book' - ie I know the author! Tam has built an incredible world of ghosts and psychics in this, and her previous book My So-called Afterlife. In this one, teenage Skye has a troubled teenage ghost who was killed in a gang shooting to help, and has her own troubles with her boyfriend, handsome bad boy Nico. A lively, humourous and warm book, and one that isn't scared to tackle big themes. The end, while satisfying, doesn't tie up all the strands of the novel and leaves you desperate for Tam's third novel, My So-called Phantom Lovelife which isn't yet published!
If you've got teenage girls in your house I'd say this series is a must.