Can't add songs to itunes!!

When I try to add songs, or EVEN get a free itunes podcast I get this:

Attempting to copy to disk "Macintosh HD" failed. You do not have enough access privileges for this operation."

This on my new mac, in which I have transfered my previous itunes library from my old mac.
What am I supposed to do to use my itunes like a normal person?

Fixed it! it was the extra account that migration assistant added, once that was removed everything worked. Don't use migration assistant just for itunes, you can just drag what you want to your new computer.