I guess you could go to the media pool and use the tool that deletes all unused media, and then click on each to read it's properties. I don't know of a way to do it from explore via the folder itself. Gonna take a sheet of 8 1/2 x 11 and a number 2 pencil. You could then create a folder for each project and move the media there. When you open the project in Vegas again, Vegas will prompt to search for the missing media. Once it's located it, you can click "yes to all" and Vegas will look there for all the other relocated media at once.

I usually capture all media for a project to a project-specific folder. And use special-purpose folders to house generic backgrounds and such. DGrob