This person is probably never coming back here, but I'll post it anyway.
It is not a good idea to post this kind of thing on a message board. Especially on MR where there are people here, who are only here, for the promo codes and freebies. I'm pretty sure she/he is getting messages from people either saying they are the girl in question, or are related/friends of her and are "willing to take it back to her" in order to get a free iPod.
You should have left it where you found it, or turned it in to the place where you found it. Sure, it's most likely someone would have taken it home by the end of the week, but that's just how it goes with these things (and as an example, someone left their TI-83 behind, just sitting outside a classroom - someone who graduated or didn't go there anymore apparently, it could have gone in the trash, but instead I used it for the six years in middle school/high school and then sold it in 2010, easily saved my parents $100).
And in most cases, if you were to call Apple about it, they would tell you to chunk it. That's what Amazon does with their Kindles anyway. They have no responsibility when it comes to you losing the device, and they don't think it should be the responsibility of others either.
Keep it. Just erase the data and throw on a case. It's not like you're taking a unique item that can't be bought for less than $100 on eBay in pretty decent condition at this point. You never know, it could have been bought at a pawn shop miles away too, there are so many possibilities.