iPod Touch lock button is jammed, How to fix?
It's stuck down and i can't get it back up, my home button stopped working a while back so without the lock button i can't power on my device.
You will probably need the buttons replaced. Sadly the 4th gen is a PITA to open and the lock button flex cable is soldered to the motherboard making replacement hard. If your volume buttons still work and you don't want to fix the other buttons, you could try to jailbreak the ipod, then you can install an app that lets you use reconfigure the volume buttons to act as the home and/or lock buttons.
hope this helps