Board Thread:Support Requests - Getting Started/@comment-24020664-20131206153520/@comment-452-20131206211758

Deleting File pages is the same as deleting other pages. :)

Help:Image_description_page talks about the File pages, but doesn't actually talk about deleting them.

I finally found a help page which actually does mention deleting files specifically: Help:Administrators'_how-to_guide. (That page wasn't easy to find, it's listed through Help:Contents under "Getting Started > Your Wikia > Admin F.A.Q.", but I had to google it before I found it.)