We report on attachment of free electrons to fullerenes C-n (n = 60, 70, 76, 78, 80, 82, 84, 86) and to Sc3N@C-80. The attachment cross sections exhibit a strong resonance at 0 eV for all species. The overall shape of the anion yield versus electron energy is quite similar for the higher fullerenes, with a minimum around 1 eV and a maximum which gradually shifts from 6 eV for C-60 to approximate to 4 eV for large n. The endohedral Sc3N@C-80 exhibits a particularly shallow minimum and a maximum below 4 eV. We model autoionization of the anions with due consideration of the internal energy distributions. The relatively low electron affinity of Sc3N@C-80 is reflected in its reduced ion yield at higher attachment energies.