The same as if you lost a wallet.
However, if wifi is on and connected you can have it play a sound.
- If you previously turned on FIndMyiPod and wifi is on and connect go to iCloud: Find My iPhone, sign in and and go to FIndMyiPhone. You can also wipe it and have it play a sound. If the iPod has been restored it will never show up.
- Change the passwords for all accounts used on the iPod and report to police
- Apple will do nothing