My itunes songs won't appear at all on my mac book On my old computer I had a bunch of songs on itunes, and when I went on my mac there are no songs on that computer even though I am logged on my itunes account. Where are my songs?
The only way that iTunes automatically syncs music between computers is if you have iTunes Match enabled. This costs $29/year.

If what you want is to have the music you have purchased from the iTunes Store available, you will have to download that music to your new device.

If you're using iTunes 12, click the iTunes Store tab in your Music view. Then click on "Purchased." You should then (presuming you're connected to the Internet) see all of your purchased music. You can download it by clicking "Download All" in the bottom right of that window.