Photoshop :: Tracking Data In The Photos

Scenario:

1. I find stock images (let's say X and Y) on the internet. Save them in a folder.

2. I use the saved stock images in an ad or as a design element in my design piece. I save out this document as a file (let's say Z).

Here is what I am trying to accomplish:

1. Automatically read the metadata or xmp data (or even tag the file with custom data on load) for images X and Y.

2. When X and Y are used in my design and saved out in Z, I want to be able to open Z and read the tagged data and be able to identify the data from X and Y in Z.

In simple words what I am trying to do is, when I use multiple image sources in a design piece, I want to be able to open my final design file and track the source files I used, so I can go back to my archive and find them without wasting my time hunting through multiple folders and hard drives.