Media url scanner - list of urls in Data Browser
Using Jamroom
Unfortunately the only way to do this (that I can see) is at a database level.
If you launch the database admin from the Developer Tools page and open the jr_jrurlscan_url table you will see the URL alongside the user_id. You'd then need to cross-reference the user_id with the user name in the user datastore.
Its a bit long winded I'm afraid.
hth