Why do I still hear the Music on my PC ?

If you copied and pasted the songs to the external drive they are still the original hard drive. You must delete them from the main computer to be truly gone.

Thanks but I started ripping the CD's after I installed the external Harddrive.
The Computer is fairly new and nothing was ever planned to be stored on the Computers Drive.

I did notice however, that inside the ITunes Advanced settings the box was checked "Copy files to Itunes Media Folder when adding to Library".
Should that be checked or unchecked?

Within iTunes click on a song and choose File/Get Info. This will show where the song file is being stored.

Thanks , your right. Somehow some of my later rips went to C. i need to fix that.
Is there a easy way to transfer them to my hard drive and off of C ?