We present the Stark energy sublevels of Nd3+ ions in GaN grown by plasma-assisted molecular beam epitaxy as determined by luminescence spectra. We correlate the photoluminescence spectra with transitions from the 4F3/2 excited state to the 4I9/2, 4I11/2, and 4I13/2 multiplets of the Nd3+ ion for above and below bandgap excitation, with the strongest emission occurring at 1.12 eV (1106 nm). We determine a splitting of the 4F3/2 excited state to be 4.1 meV. From photoluminescence excitation spectra, we also identify the Stark sublevels of the upper states 4F5/2, 2H9/2, 4F7/2, 4S3/2, 2G7/2, and 4G5/2. Photoluminescence excitation spectra reveal an optimal excitation energy of 1.48 eV (836 nm). Site-selective spectroscopy studies using combined excitation-emission spectroscopy with confocal microscopy indicate enhanced substantial doping at the Ga site.