Arduino audio project

Hi, I'm hoping to build an audio project using 8 photoresistors to trigger the sounds. Each photoresisitor will have a seperate sound file - which will play when a hand is placed over it (low light) and stop when the hand is removed. Multiple photoresistors may be covered at once, so the sound files need to be able to play simultaneously if required. I understand that Processing may be able to help here? Ideally I'd like the sounds to play through a PC. Unfortunately have no experience with Processing and very little experience with Arduino. I have the required hardware (Arduino Uno .... and I'm going to buy an adaptor(?) so that I can use 8 photoresistors), but need someone to write the necessary code (and guide me through implementing it!). Please feel free to ask if you need more information!