By the time your battery wears out, your warrenty will be expired. They do sell aftermarket Ipod batteries, and you can get intructions off the net. It costs about $25 or to have it installed, about $40. Its about the same price for a new cell phone battery.

BTW my wife has had her Ipod for 2.5 years now, and the battery is still going strong.

Dont sweat it.