Showing Edge of Dark Water by Joe R. Lansdale

May Lynn was a pretty girl from a mean family who dreamed of becoming a film star. Now she's dead - her body dredged up from the Sabine River, bound with wire and weighted down.
Her best friend, Sue Ellen, has a family meaner than May's and a yearning for something greater than she's been given. She thinks the least she can do for her friend is take her ashes to Hollywood, and place them on her favourite actor's grave.
But May Lynn's diary holds a secret: the location of a large sum of money. What seems like a stroke of fortune has disastrous consequences, and Sue Ellen's escape is about to get more complicated than she'd ever imagined.