Hmm, I dont know enough about perl myself to offer up a fix, but you have the right idea.. look into reading/writing files with perl. it should be as easy as writing a timestamp when the event fires and specifying a time limit till it can fire again.

PS, if you are doing this on a *NIX system, use mplayer. I'm not sure if there is an equivalent for windows systems, but you should look into playing .mp3s from the windows CLI, as loading up vlc to play a file is a resource hog.

EDIT: Don't use the --quiet flag