Why won't my library in itunes sync with my new ipod nano?

Right about now I am ready to throw this thing through a window. I have had a iPod Nano first gen for about 4 year. It is working fine, but I wanted to get a new one that was under warranty and that had a pedometer. I purchase a new one and now I can get NOTHING on it. No matter how it says it it syncing, nothing will download onto the **** thing. I've been screwing around with this thing all night and I've tried everything, but it just won't take any music. I'm about tot take it back and just keep my old one and screw the pedometer feature.