Every one of those can have their batteries replaced fairly inexpensively. There are usually services that will do it for you. Check out a local yellow page app. Apple's business model is not to sell you new batteries, or new models because the batteries fail. It is to upgrade the speed and functionality to make it a desirable upgrade so you want to buy a new one and sell or hand down your old one.
Not at the time. And it can be pricy too. We just bought new ipods until we figured out the game.