ITunes Library between 2 Computers?

My Dad set up a new apple desktop computer in place of our PC desktop. My iPod got water damage and died last week. I got a new nano today.

What is the best way to transfer the music from the old hard drive onto the new Apple desktop?

Is there an easier way than having to re-set up to old computer to burn all the songs onto CD's, and then replug in the new Mac to put on the Mac's iTunes library? That's the only thing I could come up with.

...Besides otherwise once again, re-setting up the old PC, just plugging in the new nano, downloading all the songs onto the nano, and then syncing it with the new Mac?

Suggestions? Is there a way to just get my iTunes library online? I looked this up online but all I came across were super complicated steps to syncing all the computers and stuff. I don't want to have to go through that. The only thing I need off the old PC is my iTunes library.