where is he at i cant find him

He's stealthed and on top of the small tower in the southwestern part of gnomeregan.

He is at 25,44. You probably won't be able to see him unless you climb the small tower.

how do you talk to onin machammer???

Yes, i am also level 10 and whenver i try to speak to the stealthed onin, it doesnt work. please help

I think this is a rogue only quest... thats why other classes can't get the quest from him

This quest is Rogue only. If you look at the quest that you can get before Simple Subterfugin', it is aquired at level 10 from the Rogue trainer in Kharanos. It says to go meet the questgiver of Simple Subterfugin' in the Forlorn Cavern in Ironforge.

location is 25,44. Head straight west from Brewnall Village and look for a platform with a spiral walkway. He's on top of it.

whenever im next to him i cant see him so i cant talk to him

Went there three different times, thinking he might be a spawn.  Never once showed up.

Oh he is there all right. SE of the main entrance to Gnomeregan. I can see him on top of the spiral tower and I'm not a Rogue. Undead Warlock actually :) So I will just pass him by....

has no one noticed? the BLACK SKIN and RED EYES didn't give it away? no?! then I shall tell you, he ISN'T a bronze beard dwarf (the playable race) he's a dark iron (sworn enemys of the bronze beards) so why is he helping allies? (P.S. I wish you could play as dark irons >.<)
 

I never knew what he was for, so I googled him, So he's the Rogue quest person..