Although Milwaukee's The Mighty Lumberhorn hasn't released an "official" CD in four years, the down-home hillbilly outfit -- that invented its own instrument and then named the band after it -- hasn't gone anywhere. In fact, The Mighty Lumberhorn returns with its second studio disc, "Lumberhorn Presents ... Nothing Ever Happened," which gets its official release with a gig at Linneman's Riverwest Inn on Dec. 19