The Infinite War series, authored by Philippe Painchaud (Dotswarlock on the GPG forums) is a succession of fanfiction books set from 20 years before the events of Supreme Commander, to the events of Forged Alliance. The books have received a terrific reception among fans of the game. The entire finished series stretches 13 books. You can access them here: https://mega.nz/#F!MhYHXSaa!VwDprTkhkjbSmszEgUlPH