The electronic and geometric properties of gas-phase exohedral C60NaN-, C70NaN-, and C60AuN- cluster anions are investigated. Time-of-flight mass spectrometry and photoelectron spectroscopy (PES) reveal complex-specific arrangements of the sodium and the gold atoms on the fullerene cage. The electron affinity of C60AuN clearly shows even-odd alternation with the number of Au atoms, which suggests a "dry" structure where Au atoms aggregate as a cluster on the C-60. In contrast, C60NaN and C70NaN show a "wet" structure having the Na atoms packed into stable trimers on the surface. For C60NaN (N = 0 to 4), PES experiments at a high photodetachment energy (5.81 eV) allow us to deduce the net charge transferred from the sodium atoms to the lowest unoccupied molecular orbital of the fullerene. For larger C60NaN, moreover, a metallic transition is shown to occur at N similar to 13, and analysis of the adiabatic electron affinity variations allows the identification of the first magic sizes corresponding to electronic shell closure in the sodium layer.