iTunes Library question

Organizing my iTunes Library I somehow deleted my 1500+ songs, it's empty! They're still on my iPhone though.

So my question is:

How do I transfer my music FROM my iPhone TO my MacBook Pro so I can restore my Library the way it was? Only 10% of these songs was purchased on the iTunes store so I already transfer those but... that didn't help too much.

I thought my music would be in the cloud but I don't even know where to find it. Not sure if it's because my iTunes Apple ID is different from my iCloud Apple ID which HAS to be a @me.com account in order to sync emails, etc.

Thanks in advance!