Everything that’s currently available can be accessed on Archive of Our Own and FanFiction.Net.
The Journals of Florimel Pines (The story of how Flora met Bill and what happened next)
The Summer of Weirdmageddon (2012)
The Liberation of Flatland (William Sifras’ origin story) This is my 2020 NaNoWriMo novel.
“Boulevard of Broken Dreams”
Other Works of Fiction in Other Alternate Universes
Shadow Falls (the author’s Gravity Falls BillFord/Stanchez universe: Dark Canon)
“The Statue in the Forest”(What happened after Ford and Stan returned home) Ongoing
“The Sanchez Problem” (Set during Ford and Fiddleford’s college years) Ongoing
Other Authors’ Universes
“The Afterlife of Liam Cipher” (set in PengyChan’s ‘Flat Dreams’ AU, a story of an alternative fate for Bill’s beloved Irregular brother, Liam. Written with permission.) Ongoing
Other Works of Original Fiction
The Dirandan Chronicles (original science fantasy universe created by the author (penname Tabitha Bradley). Elements appear in both Mystic Pines and Shadow Falls.) Currently Unavailable (may be available via a search under Tabitha Bradley or Diranda)