Unique Sets

Where/when did you get your unique set? I only have 2 unique items, a Dark Sword and a Lightning Helm. I'm level 83, in Inferno difficulty, but definitely underpowered. Want to get full sets of at least Lightning, if not Dark or Inferno.
It's all luck. For the best chance I'd say farm boss levels, I think most of mine came from those. I'm one piece short of a full inferno set and have a few extra pieces of different sets. Same goes for combining, no rhyme or reason to it, just the random chance you'll get something worth having.
That friggin sucks. Can I stay in Hell difficulty at least? I'm basically stuck and can't really progress at all, as my suggested defense for World 4 of Inferno is at 10% and the game is actually difficult again. I'm level 83 and see that people at level 50 have great gear, so surely I don't have to stay in Inferno difficulty?
You can farm items in hell as easily as inferno. When you see people at level 50 with tricked out gear and amazing stats, it's a safe bet they've cheated the game. Don't be discouraged. Remember, there are no real world prizes for this game. So play for fun and at your own pace.
I have no unique itiems. I usually farm in Dark Dungeon, i'll try farm in Hell diffculty mode, hope lucky
Bro how did you level up to 83? Currently I am at level 26.