They don't want the disc back, they just want the 2:00 a.m. harassing texts and calls to stop.
bunch of pansies up in here jeesh. vigilante justice will prevail!
Oh really? I guess I must have read Doofenwhatever's comments wrong then. Oh wait, no I didn't...
That's an awful lot of effort and outrage over a $15 dollar piece of plastic that someone clearly needs more than I do. Just sayin...However, if the thief (and they are a thief if they take a disc that they know belongs to someone else) were to call me to harass me as described by the OP, I'd go visit my local law enforcement agency of choice and have the dumbass receive a call. In my area, I'd most likely also visit with the park officials and advise them of the situation. I'd bet even money that I could get the thief/dumbass banned from the park if he didn't return the disc along with an apology.
I'd probably also document the whole thing somewhere on the web, names and all.