my ipod is locked will the apple store charge me

They will not charge you.

Make an appointment at the Genius Bar of an Apple store.

Apple Retail Store - Genius Bar

You can try yourself:

If you previously turned on FIndMyiPod on the iPod in Settings>iCloud and wifi is on and connected go to iCloud: Find My iPhone, sign in and go to FIndMyiPhone and use Remote Wipeto erase the contents of your device. If you have been using iCloud to back up, you may be able to restore the most recent backup to reset the passcode after the device has been erased.

You can also wipe the iOS device by installing the FindMyiPhone app on another iOS device and using that app to wipe the device

or

Disabled

Place the iOS device in Recovery Mode and then connect to your computer and restore via iTunes. The iPod will be erased.

iOS: Forgot passcode or device disabled

If recovery mode does not work try DFU mode.

How to put iPod touch / iPhone into DFU mode « Karthik's scribblings

For how to restore:

iTunes: Restoring iOS software

To restore from backup see:

Restore your device from an iCloud or iTunes backup - Apple Support

If you restore from iCloud backup the apps will be automatically downloaded. If you restore from iTunes backup the apps and music have to be in the iTunes library since synced media like apps and music are not included in the backup of the iOS device that iTunes makes.

You can redownload most iTunes purchases by:

Downloading past purchases from the App Store, iBookstore, and iTunes Store

If problem what happens or does not happen and when in the instructions? When you successfully get the iPod in recovery mode and connect to computer iTunes should say it found an iPod in recovery mode.