The Dead Club - Manuel Ruiz

Grey Gomez is an eleven-year-old boy who is having a bizarre week.  First he dies, then wakes up in the afterlife with a tomboy, a baseball player, a beauty queen and a science geek.  They learn that Purgatory is broken and are soon thrust into a frantic search through the Underworld to find out why.

With the help of an Oracle and the Grim Reaper himself, Grey and his new friends develop extraordinary abilities that aid them on their quest to discover the truth.