Acquiring your Epic Set
First off, a lot of people call the Epic set Elite. There is no right term, for the achievement "Relics of a Forgotten Past" contains the word "Elite" while the strategy guide by Prima calls them "Epic." Just know when seeing topics containing the words "Epic Set" or "Elite Set", that many people mean them to be interchangeable and are indeed talking about the 7 piece set that is only for your class and alignment. That said, here goes.
Acquring your Elite Weapon
Some people have gotten their Elite weapons off of bosses. I got mine (a blue print) out of an obelisk in Aesir. They can also be found off of bosses as I have found the Human Commando Elite weapon and the Human Champion Elite weapon off of Grendel.
The easiest way to get your Elite weapon is at the weapon shop in Aesir. Load up a game, go to Tyr's Workshop and search through the weapons. If it is not there, select "Quit Game" from the menu that appears when you press "Start". Load a game like before, and repeat until your Elite weapon appears. Note, however, that you will have to pay over a million Bounty for it, so be prepared for that. Some people have seen their weapon in there and not had enough bounty and went to a mission thinking they could go back only to find that the weapon selection is different after the mission is over.
Acquiring your Elite Armor Set
If you aren't prepared to sink some hours into getting these pieces, don't bother trying as this can be a quest that tests your patience and sanity. There is no such easy way of acquiring your armor via the Armor Shop as there is of getting Epic weapons from the Weapon Shop. You have to either receive them from drops which are blueprints you must craft, or trade for them.
First we will discuss the old-fashioned way: Grinding for them. I am patient to a fault and I wanted to rip my hair out at various points trying to get my epic set this way, but it was rewarding after I did it.
Firstly, a Note About Tokens
Think of tokens as checkpoints in a way. When you complete a certain section in a level, you earn a token. For instance, The Hall of Heroes is broken into 3 sections, 1-1, 1-2, and 1-3. By completing 1-1, you will receive a token. By then playing on in the level, you will get another for completing 1-2, and so on and so forth. The importance of tokens cannot be stated enough. The more tokens you have, the more likely the Boss (and, in some cases, Elite enemies) is to drop an Epic Blueprint. Long story short: If you think that you can do 1-3 over and over to skip most of HoH to do Grendel runs, you will not likely ever get an epic piece.
I acquired my first piece off of Hel, the final boss in Helheim. I then started to do Helheim runs and got one more piece after about 5 more runs. However, Helheim can take quite awhile to beat, so at the advisement of others here on GameFAQs (thanks guys), I then switched to doing Grendel runs on Hall of Heroes. After a good 25 or so run-throughs of slaying and re-slaying Grendel, I had all of my set. I can also quote the dialogue of the Berserkers, Baldur and the Wolves like a preacher quotes Scripture, so be prepared for a lot of runs if trying this method.
1. The Grendel (Hall of Heroes AKA HoH) method of acquiring your epic set:
The easiest thing to do here is select "Continue Campaign" from the main menu and while in Aesir, go to one of the many terminals and select "Replay a Past Level" from the terminal. Then, select Hall of Heroes and start from the beginning (1-1). Remember, you want as many tokens as possible so the Boss and Elites will have a higher chance of dropping an Epic Blueprint. Play through and skip anything unnecessary such as secret arenas and wells, to save time. Unless you want to actually do all of that for bounty or other drops, but not doing the extra stuff will save you a ton of time. Run staright through to Grendel and pulverize him. He's pretty easy and quick to get to (provided you skip unnecessary wells and arenas). I got the remaining 4/7 pieces needed for my set off of him over 25 runs in 2 days. i have also seen people while playing co-op with me receive a piece of their Elite set off of the Elite Goblins ( the ones that rush at you a lot faster than the others and ususally have a red shield around them) and off of Grendel. I played by myself just because the drops are hard to get to drop in the first place, and I didn't feel like competing with others for them.Others also swear by making a co-op game and setting the 2nd slot to "Private" and playing through alone. The logic here is that there will be more enemies, hence, a higher chance of an Epic Blueprint drop.
2. The World Serpent (3-4) Conveyor Belt Runs
This method involves going to a terminal, and selecting World Serpent 3-4 from the level select list. What this allows you to do is to access the conveyor belt area quickly and the great thing about the belts is that they are chock full of Elite Goblins. I have never done this myself, as I already had my epic set before I found out about it, but it seems to work for a great number of people. On the conveyor belts, many Elite Gobs will rush you, and they all have a much higher chance of dropping an Elite than regular Gobs. Fight them all, and Quit then reload it again until you have some sweet Epic badassery. The downside of this is that you don't have all the tokens, and that probabaly hinders your drop chance for an Epic, but this method makes up for that because you can do this fairly quickly over and over again.
Trading for Elite Equipment
These are guidelines and there always exceptions for trades depending on what people want/need, but for the most part, poeple adhere to these behaviors and methods.
Firstly, offering Bounty is usually a complete waste of time. I have never duped, or been given anything, and have over 18 million Bounty. Bounty is worthless, since it is so easy to acquire. "Duping", the process of duplicating items that was not intended by the makers of the game, has also rendered Bounty even more worthless since there is so much floating around.
Secondly, usually offering Epic Weapons is a waste of time too, unless the person doesn't wish to load a game, check Tyr's shop, and quit, and re-load etc. There are far more Epic weapons floating around than Armor. Most everyone is not willing to part with their Epic Armor for runes, or charms either.
Usually, if someone is willing to part with a piece of Epic Armor, they want a piece of Epic Armor from another class, or they want Aesir Armor in return. Aesir armor is armor that usually has 3-4 open Rune Slots, thus highly customizable and depending on which runes are inserted, sometimes better than Epic Armor.
I'm not saying you shouldn't pursue trying to trade weapons or runes or bounty, but be prepared to read what the Trader wants, and act accordingly. It gets old telling people that you don't want bounty or weapons when you stated that in the first paragraph of the post. That being said, many traders will list what they have and pretty much say " Make me an offer." In that case, I'd go for offering bounty, weapons, Runes or Charms.
I didn't make this because I feel "Elitist" or anything. I made it because I genuinely want to help people with their acquisition of Epic items and just cannot do so because there are so many topics, it would take me all night to try.
Remember, Epic Armor requires a large amount of patience, and it will pay off. Keep at it, and good luck!
-runJebus also added If you're a berserker, and therefore running the conveyor belt instead of farming the spider, don't play from the campaign. Use multiplayer, set up a game and close off the 2nd slot. This increases the amount of named goblins (the guys that can drop reds) on the conveyor belt.
I have not tested his method myself but if you're having problems acquiring your set you might want to try this route and see what you come up with.