STARS ARE WIDELY UNDERSTOOD TO FORM FROM MOLECULAR GAS SO KNOWLEDGE OF THE MOLECULAR ISM IS A KEY INGREDIENT IN UNDERSTANDING GALAXY FORMATION. EMISSION FROM THE HCN MOLECULE HAS BEEN INVOKED BOTH AS A TRACER OF DENSE GAS AND OF EMBEDDED AGN. WE A PURSUING A MULTI-WAVELENGTH CAMPAIGN TO UNDERSTAND THE ISM AND NUCLEAR ACTIVITY IN LOCAL IR LUMINOUS GALAXIES. WE HAVE IDENTIFIED STARBURST GALAXIES WITH HCN ENHANCEMENTS (RELATIVE TO EMISSION FROM HCO+) SIMILAR TO THOSE SEEN IN AGN SUGGESTING THEY MAY HOST COMPTON-THICK AGN. WE REQUEST NUSTAR OBSERVATIONS OF FOUR TARGETS TO DETECT OR PUT STRINGENT UPPER LIMITS (# 1% OF LBOL) ON BURIED AGN. THESE DATA WILL BE USED TO IMPROVE OUR UNDERSTANDING OF THE EXCITATION OF DENSE MOLECULAR GAS TRACERS AND TEST THIS PROPOSED METHOD OF FINDING BURIED AGN.