What are some of the best places to farm Trolls in Moria. There must be more than the occasional Elite, I'd expect. I was thinking somewhere in The Foundations of Stone, but I don't know where to look in there.
There are a few in Nud -Melek on the west side on sides from the stairs. Foundations of Stone. The Skirmish - Battle of 21st Hall has Trolls. There always one in the Way of the Smiths Skirmish - if you get the Troll encounter you will have two.
Unless stated otherwise, all content in this post is My Personal Opinion.
Forges of Khazad Dum has about 8 too I think, I used to get more when the group wiped on last boss, but it'll be a rare occurrence now, with L75 people.
Battle of the 21st Hall skirmish has Trolls, but they spawn unreliably. You can get 12 Trolls per run or you can get 1.
When all else fails, go to Foundations of Stone to kill Globsnaga Trolls.
Troll deed in it's best is in Forges instance. You kill all bosses and when you reach the last one, he always have 2 trolls with him. You kill those 2, and reset the boss. Repeat and win
See, if it's only really worthwhile to complete the deed when it's in an instance, why didn't they make the Troll Deed an instance deed, rather than in the field.
There are multiple options for finding them, which for me makes it more fun than just grinding the same one instance over and over. You can get them in GS, DN, and Forges, or Foundations of Stone while questing or exploring down there.
I got about half of mine in GS, and the other half running around Foundations (there are plenty down there, just go get yourself lost and you'll run into them). Of course, after solo-grinding in Foundations and finishing the deed, I realized I hadn't done the deeds for trolls in Forges or DN...*facepalm*
The trolls in DN won't count for the Moria troll deed unless you go in in a 6-man fellowship, which is still kind of tough even with a group of 75s only. As soon as you are in a raid (even a 6-man raid), kills won't count towards deeds except for the few kill deeds specifically tied to a raid instance.