Youtube to mp3 is good. Just copy and paste the link from youtube to the mp3 converter and it downloads to iTunes. then u sinc it.. you could also use any of your CD's you have> you just burn it onto iTunes and you download it to your ipod. i wouldn't recommend jailbreaking or downloading apps like BEARSHARE because they're illegal & if u get caught, you can get fines for jailbreaking and you can pay up to 3 THOUSAND DOLLARS PER SONG from sites like BearShare :S
There is an app you can download to download music videos and movies from youtube or any website. Just look up free video downloads in the app store of you ipod. The best one is multi clip. Others only allow 5 downloads that one has no limit plus it's FREE.