Photon help for a noob!

Hey there. Let me say first, the documentation was a hard read. I need two pieces of advice. First about ray casting, should I only initiate the raycast on one client and tell the other client he has been hit, or tell everyone on the server to initiate the raycast and check if they themselves have been hit. Next is some code advice, if you knowa. Better documentation link please. I am hoping this question should provide some good for thought so I can finally crack the networking egg. Playing a shoot sound multiplayer, I know I probably need an RPC for this but I'm damned confused on how to get it 3d sounding. Like, if the guns behind you it sounds behind you. If they then walk Infront of you it sounds Infront of you. Code based answers for this part are happily accepted as hopefully if I get this I should be able to understand anything.

Regards In advance Strideynet Typed on an IPad so accept my crappy spelling.