John Miles – Music

How do I get my music to save to the iTunes library?
I download my music form Frostwire(same thing as Limewrire). I get the music in the library and it goes to my iPod and everything. The next day when I go to iTunes, the music is not in the iTunes library BUT it is still in my iPod and everything. The only way I can listen to music on iTunes is if i plug in my iPod. Otherwise there is no music on the library. What can I do?

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