Is there any place I can download more voices?

So I was bored and was fiddling around with iTunes, when I found that you can put voiced menus on it. It was random and sorta niffty so I put it on it, but there was only one problem; It only works with English. Because I switch the languages on my iPod a lot (I do this mainly out of boredom, since the iPod has so many pictures, I don't really even need it to be in English.) I wanted a voice that could speak other languages on my comp. Does anyone know where I can download new voices for Windows Vista? Especially those that I can use when I switch the language, but a new English voice wouldn't be that bad either. Ty.​