First, make sure it is charged 
Second suggestion is try resetting it.
Hold down the menu button, and the center select button, until an apple appears, once that happens, the ipod has been restarted, and should turn on like normal.
I had the same problem before when I thought my Ipod nano suddenly wont turn on. Where do you charge it? Through USB in your pC? Was it drained of its battery completely? IT may be the cause. Try charging it externally using a wall charger or bring it to an apple store to check if it charges using an external charger as charging through USB in a PC cant recharge it if its completely drained.
If it still will not charge, then have ti checked and repaired as you are still eligible for the 1 year warrranty but not the replacement I guess.
@Jill75 wrote:I had the same problem before when I thought my Ipod nano suddenly wont turn on. Where do you charge it? Through USB in your pC? Was it drained of its battery completely? IT may be the cause. Try charging it externally using a wall charger or bring it to an apple store to check if it charges using an external charger as charging through USB in a PC cant recharge it if its completely drained.
If it still will not charge, then have ti checked and repaired as you are still eligible for the 1 year warrranty but not the replacement I guess.
You can take it to Best Buy and have them try resetting it.
If you are going to charge it through the computer, you'll need to make sure the computer is on.
Or you'll have to buy a wall charger.
