Complex sentence: The label released its first ever "mixtape", entitled "Golden Era Mixtape 2011", on 17 January 2011--it contains musical contributions from the Hilltop Hoods, Funkoars, Briggs and Vents.
Split into simpler sentences: The label released a "mixtape" entitled "Golden Era Mixtape 2011" on 17 January 2011. It contains music from the Hilltop Hoods, Funkoars, Briggs and Vents.