When LotRO: Shadows of Angmar was released in 2007, only the first eight books of the epic story were available for players to experience. There's no getting around it - the first few books aren't well connected at all. It's almost as if they're completely different stories, held together only by the tiniest of threads.
Starting out in Breeland, you meet Strider, a ranger of the North, who is revealed to be Aragorn. He sends you on a quest to see what happened at Crickhollow after investigating what's left of the Blackwold brigands. For anyone who's read the books, Crickhollow was the temporary home of Frodo Baggins after he left Bag End. You'll eventually meet notable characters like Tom Bombadil and even Gandalf himself by the end of book one.
By the time you return to Aragorn, he's left with the hobbits in his care. You'll head towards Weathertop, only to find that there was a terrible battle waged there only a few nights before your arrival. The following few books introduce you to the Rangers in the North, headquartered in Esteldin, and Elrond in Rivendell. Book five concludes the Skorgrim story arc. You'd think that victory over the evil, undead dwarf would provide some relief, but you'd be wrong.
Books 6-8 take you into the dark realm of Angmar, which used to be the kingdom of the Witch-King many hundreds of years ago. Mordirith, an old king turned wight, has taken the throne for himself, and he desires to command all of Eriador. The ranger Lorniel leads you on a quest to free her father, Golodir, and is killed in turn. At your most desperate, you defeat Mordirith.
Upon the game's release, Mordirith was the end game boss, and the Carn Dum instance took hours. The dungeon's been scaled back to fit in line with the other epic quests, and players can only wistfully remember how much more difficult the old instances used to be.