I own an iPod 3G and have over 3.000 songs in it downloaded from my old computer. I bought a new laptop recently, installed iTunes and downloaded some new additional songs. I tried to upload them into my iPod but iTunes gave me the option that to download the new songs I'd have to erase the existing 3.000 songs I had already downloaded from the old computer. Is this right? Shouldn't iTunes automatically add the new songs without deleting any previous files I've already added?