Turanil said:
(I already added a few lines about the races of the continent).
The SRD races by environment:
Warm Plains: Halflings, Gold Dragon, Gnoll (including underground lairs with trolls)
Warm Mountains: Storm Giants (plus griffins and sea cats), red dragons, fire fiants (plus ettins)
Warm Marshes: Black dragons, rakhasha
Warm Hills: Copper dragons, hobgoblins (plus ogres and trolls), deep halflings
Warm Forests: Ettercaps, couatel, yuan-ti-clone (?), wild elf
Warm Desert: sphynxes, brass dragons, janni
Warm Aquatic: Locathah/Shaulin
Temperate Plains: goblins, tieflings, worgs, aasimir, blink dog
Temperate Mountains: dward and mountain dwarf, cloud giant (and griffons), silver dragon, giant eagles, bugbear, stone giant, gray elf
Temperate Marshes: hydta, lizardfolk
Temperate Hills: ogre, gnome, bronze dragon, hil giant, athach, orc, chimera,
Temperate Forest: green dragon, dire wolfs, grigs, unicorns, aranea, centaur, kobold, nymph, pixie, dryad, satyr, treant, giant owl, (high) elf, wood elf, forest gnome, tallfellow halfling, kobold
Temperate Desert: blue dragon, lamia, dragonne, dire bat, lammasu
Temperate Aquatic: sea cat, kraken, merfolk, triton, nixie, aquatic elf
Cold Mountains: troll, frost giant (plus ogre and winter wolf), white dragon
Cold Aquatic: Scrag troll
Cold Marsh: ogre, ettin
Cold Hills: ogre mage, ogre, orc, ettin
Cold Forest: winter wolf
Any: doppleganger, human, gargoyle (plus aquatic)
There are lots of minor races to fit in.
There are also a lot of environments to fit in, and I'm not sure where each goes.