Eoin Colfer 
Half Moon Investigations [EPUB ebook] 

Meet Fletcher Moon. Half-pint schoolboy and fully qualified private investigator. Since graduating online, he has solved all sorts of minor mysteries at school and at home. It was only a matter of time before things got serious. When Fletcher investigates a spate of crimes in the town of Lock, the finger of suspicion is soon pointing in the direction of shady brothers Herod and Red Sharkey.