I figured I'd write this as a reference for an IRC channel I op as quit a few people wonder how to Scrobble from an iPod Classic.
You need a few things:
2. foo_dop.dll - http://bit.ly/dBI3Cm
3. foo_audioscrobbler - http://bit.ly/cRBrGj
Place both dlls in your components folder and then restart foobar.
In File>Preferences select Audioscrobbler and fill out your username and password, the click "Import played tracks from portable devices". You should then be able to sync your iPod by going to File>iPod and clicking synchronise. You don't have to fully synchronise it though check out View>Console to see if there are any problems or how many tracks you've scrobbled.
And that's it, enjoy!