There is a store here in a suburb of the nation's capital called Rockville, md named Batterie's plus that claims "If it runs on batteries we got it." They claim to have the battery for the kindle three for $25 + $10 if you want them to do it so that you ensure that the battery is in right. That's a saving of $85-$35 = $44 over the cost of the replacement cost. However I firmly believe that with the drop in the prices of ebook readers, the reades are quickly approaching what I referr to as the disposable point - this is the point where it will cost more to repair the old one then it will cost to replace the item. A common houosehold electronic that is currently past that point is the common household calculator, which can cost $5 for a new calculator and the cost of the new battery will be somewhere in the region of $8, making the cost of the replacement less then the repair cost - in other words that old calcuator has just become disposable.
By the way batteries plus has a web site at
http://www.batteriesplus.com/manufac...r-Battery.aspx - this is the section that is dedicated to electronic readers. I believe they will ship you the battery if you do not happen to live near one of their stores.
I was told when I first got my kindle that the battery would last longer then my willingness to stay with that model of electronic reader. I was told that I will have long upgraded to a newer model of electronic reader by the time my battery on my old one dies and as seen above the battery can be replaced on the reader.