Help please, Newb problems.

Hello,
I have been attempting to keep all my iTunes files on an external hard drive and I have had no problems, however, my girlfriend has been adding files to the itunes on the computer hd and today, I attempted to merge the libraries.
I thought that everything had worked. I followed a tutorial I found on the support site. The last steps of the tutorial suggest taking the itunes files from the hard drive and dragging them to the trash and then emptying the trash. I dragged it to the trash, went to open itunes through the new path, and what do you know, it told me that the folder I had created on the external hard drive to house the merged libraries didn't contain itunes. Arrgghh! It appears that I have erased everything!

Fortunately, I didn't empty the trash, and I pulled the itunes folders out and copied them to the external hd.

I am confident that both libraries now exist on the external hard drive, but because I merged them to a new folder ( at least I thought I did) that won't work, I'm not sure what to do.

Does this sound like a normal problem with a simple solution? I am a bit frustrated and not thinking straight, can anyone make any suggestions?

I would appreciate your advice. Its my first Mac and I guess I just don't know what I'm doing.

Thanks in advance.