[Soran]

Aww... I feel your pain. Too bad these people probably wouldn't even read this post :/

I for one would just ban such users on the spot. I mean c'mon, it's common sense that one should at least try to contribute something before making a request. Sending a request per PM before you contribute anything is plain rude. Asking for other people's sources per PM is rude regardless of your contributions unless the one you're asking is your close friend.