I think Apple adapters are all 100-240V, 50-60Hz - which means, on the electric side, they should work as well in the US as in Europe -.
Now, you will need to change the physical plug part - and you might even already have a spare one in your drawers from some other device.
NB: There's no guarantee I'm right here, I hope you don't toast your iPod ! But the "100-240V, 50-60Hz" should be written on the adapter. I bought my own iPod in Tokyo, and use it in Europe (the Netherlands, which has the same plugs as all Western Europe at least).
Hope that helps...