My 4th gen ipod won't turn on.

My ipod turned off (battery died) so I plugged in to charge and left it for a few hours, when I came back to turn it on nothing happend and it doesn't show it charging. I tried several different cords/charging ports (including my computer/wall outlet) and it does not charge at all or turn on. I've searched some sites/google looking for ways to try and fix it but only thing I've really seen is to press and hold the home/lock button together for a bit, but it doesn't do anything. My ipod appears to completely dead.

So I'm looking for any insight as to what may be the issue and how I can go about trying to fix it. Would I be able to identify a/the issue by taking it apart? Is there something I should try replacing?

Several months before this happened the screen cracked in the top right corner when it fell onto the road. There's a small area at the top corner of the crack that's open to the inside of the ipod. It may be possible that some sweat got in when I was using it while working. If this is my issue is the whole thing basically scrap or can I just replace a damaged component?

Sorry for the messiness of this post, and thanks in advance!