I recently started using Cross References Pro by DTP Tools. It's so powerful that I had a hard time figuring it out at first. Once I figured it out, I decided to make a quick-start video to help others who were in the same position of not knowing where to begin.
Here are links to some of the cross References Pro pages on the DTP tools website.
Cross References Pro Product Page
List of Cross References Pro XML Elements
Cross References Pro Product Forum