How can i put more music on an ipod from my computer without deleting the music that is already on t

my stepdad bought an ipod video and i put music on it for him, then a couple of months i got one and deleted all the music from the library and put in the music for my ipod, now i want to put music on my stepdads ipod but im afraid the music he has on his will get deleted

How can i put more music on an ipod from my computer without deleting the music that is already on that ipod?

-(Myspace music www.myspace.com)

No just sync using the iTunes, you won't delete anything. If in fact if you want to be extra cautious, make a copy of the songs on the ipod before you sync.

iPod gets detected has an external Hard Drive on your computer, so just go to My Computer and see the iPod folder and copy all the songs to another folder on your C:/, try not to use the same folder as music or itunes, so you don't get confused.

and then let itunes search your HDD for all the media files and then it syncs automatically.