where is he? please, i have looked everywhere. probley in plan site
Usually, when you have a quest to "talk to someone", that character is highlighted by a yellow circle on your map. Try pressing "m" and check your map.
Just in case, for some reason if he isn't showing on there, I couldn't find a map that actually shows where he is, but this might help.
When you enter the Crustacean Empire, you can see Nestor standing in the middle of the first area. Go up the ramp behind Nestor, and you will see the two Teleporters. Go past the two Teleporters, and there is a "black" doorway. Go through that doorway, and you will see Thurston Plunkett.
This link shows a map of the Crustacean Empire in case you need it (Nestor is right at the green arrow on the map):
You can find the room he is in behind the teleporters in the Crustacean empire. An easier way is to turn on quest helper and follow that or look at your map (it should show him on the map since you have a quest to talk to him). Good Luck! Saffron Sandsword Legendary