nano (5th gen) and Winamp

When using Winamp to transfer music to my ipod all my music transfers fine but when I eject the ipod and check for the transfered music... nothing is there! I have tried with another program with the same results. When I check the ipod through window, I do find files on it (the music files) but they are not named and stored under an "other". When I click on the file it opens winamp and plays. And it will then show it in winamp under ipod. If you stop the file from playing and then try and replay by clicking the file under ipod in winamp it does nothing!! Please help.