Gongs or Gongers
 

Both in TME (Tolkien Monster Encyclopedia?) there is an entrance for Gongers, which are said to be like goblins. This same definition is given in a Tolkien quiz. Does anyone have a book reference?

Specification
 

Allthetests.com:
Q: What were the evil creatures related to Orcs?
A: Gongs

TME:
Gonger: Evil creatures, related to Orcs.

This is an interesting question, Makar! The word sounded so strange and unfamiliar to me at first glance that I thought it was another of those D&D type game inventions. However, looking it up in my Index to HoME, I found that it refers to The Book of Lost Tales (HoME I and II). In an early version of the Legendarium, Tolkien used the word. In BoLT 1, CRRT's notes at the end of the chapter 'Gilfanon's Tale': In BoLT 2, there are a few usages of the name and another note at the end of the chapter 'The History of Eriol or Aelfwine': Since the word is not used in any later versions of the stories, it appears to have been rejected by JRRT; however, the 'Gongs' are a genuine invention of his!

since were on the topic of orc and that sort, is a cave troll anything different from the 3 trolls in the hobbit?

Trolls,
 

As far as I know there are Cave Trolls, Hill Trolls, Stone Trolls (Bill, Burt & Tom), Mountain Trolls, Snow Trolls, and the Olog-hai. I'm not sure where all this information comes from, though.

Treebeard said that Trolls were made by Morgoth in mockery of the Ents, as he had made the Orcs in mockery of Elves, however, I don't think that Tolkien meant that Ents and Trolls were related.

In letter 153 Tolkien wrote:
So I think that he intended Stone Trolls such as Bill, Burt and Tom, to be entirely different from the other Trolls.