Giammarco rhymes with:
airco, amerco, anadarko, arco, arko, asarco, barco, barko, barkow, calarco, chirco, comarco, darco, delbarco, demarco, dimarco, dorko, fedorko, marco, marcoe, marko, markow, minorco, moorco, narco, norco, porco, sammarco, tierco, trimarco, uarco, varco
Giammarco sounds like:
gainers, gamers, genereux, generic, generics, generous, genres, genrich, guimaraes, guinarou's, guinier's, gunners