I spent some time decoding the SINF files that I discussed here, thanks in great part to a link sent to me by a colleague (Thanks, Derrick). Here are my findings, to date:
Unlike iTunes Purchased MP4 media files, the SINF does not contain the iTunes user account name, which is most often their email address and most useful for contacting owners of stolen devices. Instead, you are limited to the iTunes user's name and iTunes ID#. Short of a search warrant or subpoena, Apple is not going to reveal the owner's personal information, though they have contacted owners on my behalf in the past.
Please review the data in the table and compare with your findings, if you are so inclined. Post a comment if you have more insight, find an error, or can confirm any of the information.