I think what you meant to say was that your 4G iPod has 4000 songs that you bought and you need to know how to get your music off the iPod onto your computer.
Well in that case, since it's music you aquired legally, use this:
http://www.softpedia.com/get/IPOD-TOOLS/Multimedia-IPOD-tools/iDump.shtml
It's called iDump. It's free and easy. It also supports playlist.
I received a 4th generation iPod from someone who upgraded. They had approximately 4000 songs on the iPod. Is there a way to get these songs into my iTunes library? If so please be very specific as I don't want to lose any of the songs on the iPod.
Thanks in advance for all of your help.

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