in addition to the previously listed -665, +720, +22 ( which I can confirm along with the trap and ph spawn of A Mudfilled Earth Golem - not Mudified), I found traps and ph's at : -970 x 725 x 20 and -210 x 510 x 12 and -450 x 385 x 12 and -50 x 670 x 12. Pretty much all along the west wall, several traps.
The correct spelling for this NPC is "A Monstrous Earthwalker", not "A Monsterous Earthwalker".
[Mon Mar 22 04:37:57 2010] Targeted (NPC): A Monstrous Earthwalker
I found it already up on the western wall of the zone, at location (/loc): -665, +720, +22 .
I believe this is a spawn trap spot, with the PH name "A Mudified Earth Golem", as that mob spawned while I walked over it, at the same location as this named (A Monstrous Earthwalker). Likely there are other trap locations for it but I have not found them.
The spelling fix was implemented for EQPC, but he's still his old misspelled self on Al`Kabor (Hence the spelling in the picture above). He is indeed a trap mob that has a chance of spawning at 4 other locations. All the locations are on Western half of the map, ranging from directly between the Vine Ring platform and the Western wall to the areas south and west of the Mud Ring temple.