I've been playing on hell for a while now and people tell me you get the unique torches from uber Tristram. How does one get there? Are there certain monsters i have to kill? Do I have to be a certain class or is there a preferred class that does it better than others?
You need to get 9 keys, 3 each of Terror, Hate, and Destruction from The Countess, The Summoner, and Nihlathak in Hell. These will allow you to open 3 red portals, where you will fight Uber bosses to get three more special items. Putting these 3 special items in the Cube will open the portal to Uber Tristram.
Here are the details from the wiki
As per the Diablo 2 Wiki:
Obtaining items for Uber Tristram
Once you have all three, put them in the Cube, and transmute them. If you are in Harrogoth, on Hell difficulty, a red portal will open to one of three random areas:
Each one has a boss at the end that will drop one of the three items you need. Be warned, these are much harder than Hell Baal. The bosses are, respectively:
The portal that opens is random, but combining more than one set of keys in one game will not open a portal to an area you already have open. As such, getting three of each key is recommended.
Once you have killed all three bosses, you have the items needed to go to Uber Tristam! Put them in the cube and transmute. The new red portal will go to Uber Tristram.