O'Reilly Network: The Care and Feeding of Your iPod [Jul. 29, 2003]: "10. The Replacements
There comes a time in every battery's life when it just won't hold a charge. Don't take it personally--it's just the nature of chemistry. Age, the amount of use, and the number of charge cycles all affect a battery's overall life span, and sometimes, you just get a dud in the first place. If you find your iPod is barely holding a charge and constantly flashing the Low Battery icon at you, take action. If you're still under Apple's one-year warranty, contact them about the problem. There's an online form at https://depot.info.apple.com/ipod/index.html. Even if you're beyond the warranty, you can get a repair estimate from the company and decide it you want to mail your Pod to the doctor for a battery transplant.
If you're a fearless do-it-yourself user or just want to save some money, you have other options. If you have a 2001 or 2002 iPod, you can get a replacement battery to install yourself for $59 at http://www.ipodbattery.com. You can also get a new battery for the same price at PDASmart.com. But if the thought of prying open your Pod gives you the heebies, PDASmart has a mail-order service, wherein you mail your iPod to them and they swap in a new battery and mail it back to you for a mere $68. Details are at http://www.pdasmart.com/ipodpartscenter.htm. "