iRiver H320 players use a Toshiba 1.8" drive, which you can find on eBay. (A 20GB drive, which is a minimum size, but the *only drive which fits an H320*, is a model MK2004GAL 20GB 4200RPM 1.8”) It is not hard to replace the hard drive, although the battery is a lot more difficult to replace. Here (http://www.videojug.com/film/how-to-replace-the-battery-in-your-iriver-h320-or-h340) is a video on replacing the battery. You won't need to go as far as the battery, but the video clearly shows the hard drive being removed. Believe me, this is much easier than taking the battery out!
Good luck!
Steve, June 2008