The locations for monsters stay the same, so if you remember the last time you found a creature somewhere it wont change. I'm fairly certain aside from the hidden grove(the starter region with all the biomes) each hex on the map only contains one location, one monster each. The locations themselves seem kind of random, like the artwork for the location was made and where you find the monster is just kind of plopped down somewhere. Like you said just use the directions it gives you to triangulate where to find the monsters.