I really liked Grey Griffins: The Relic Hunters.
It is about kids living a little like Harry Potter, half magical / half not. the Grey Griffins are Max, Natalia, Harley and Ernie. Together (with oters) they try to stop Von Strife, a guy collecting souls from kids. Von Strife already killed two kids (in the last book) one being Ernie's friend, Robert. Now he is about to kill another kid, Hale. Can Ernie and the others stop him???
I think that every Harry Potter lover should read The Relic Hunters because it's pretty similar to Harry Potter. It is also a must-read for every person interested in fantasy . . .