While in your Word document, place your cursor where you want to attach the file(s). Then click on the "Insert" tab at the top. Click on "Object" and then select the "Create from file" Or "PDF file" tab. "Browse" and select the file you want to attach and then check the "Display as icon" box. Finally, click the "OK" button. That should do it.
To extract it, Double-click on the "icon" in the word document - it will open in the end user's default PDF viewer. I assume that the recipient will be able to save the document using their default viewer, using file--> Save as but since the end user's PDF viewer is not specified, I cannot be more specific. 
