Well, my best guess for LotR would be:
Gandalf: Epic "Human" Wizard with Initiate of the Faith, plus an Outsider/Angelic/Saint/Istari template
Aragorn: Paragon Human Ranger with Student of Battle, or Ranger/Warlord (maybe Half-Elf Ranger with Student of Battle + one other multiclassing ability from racial perks, due to being Dunedain)
Boromir: Paragon Human Fighter with Student of Battle
Gimli: Paragon Dwarf Fighter with dwarf-developed Paragon path
Legolas: Paragon Elf Ranger (archery) with elf-developed Paragon Path
Frodo: Heroic Halfling Warlord (or maybe a Bard, if there's no spellcasting for bards per se, due to a Bardic Knowledge-like ability from his education), advancing into Paragon with the Ringbearer paragon path/template (not "full" like Gollum's, though).
Sam: Heroic Halfling Fighter
Merry: Heroic Halfling Rogue with Student of the Sword (from his service to Theoden)
Pippin: Heroic Halfling Rogue with Student of the Sword (from his service to Denethor)
Eowyn: Heroic Human Fighter
Eomer: Paragon (low) Human Warlord with Student of the Sword
Faramir: Paragon (low) Human Warlord with Student of the Sword
Bilbo: Paragon Halfling Rogue (and, like Frodo, with a bit of Bard due to his education/knowledge)
Elrond: Epic Eladrin Cleric with Student of Battle (maybe Student of the Sword)
Galadriel: Epic Eladrin Warlock (fey pact) with Arcane Initiate (maybe multiclassed into Psion/Psionic class, since that's where the major enchantments are to be)
Gollum: Paragon Halfling Rogue with Ringbearer template/paragon path (complete).
Saruman: Epic "Human" Wizard with Pact Initiate (due to alliegiance with Sauron), plus an Outsider/(Fallen) Angelic/Saint/Istari template
Grima Wormtongue: Human Rogue, trained in Diplomacy
The Witch King: Monster/Epic Human Warlord with Greater Ringwraith template
Ringwraiths: Monster/High Paragon (or low Epic) Human Warlords or Fighters with Student of Battle with Ringwraith template
The One Ring with be an phylactery for Sauron, with the Ring of Invisibility powers (or a long-term duration Ring of Vanishing/Greater Invisibility, since the Ringwearer can attack while invisible with no problem), plus it would bring the wearer into "phase" with the Shadowfell (though still being "in phase" with the Prime Material Plane).
Lothlorien would be a "pocket dimension" of the Feywild (attractive to the elves/eladrin, but not the full-blown realm they desire to return to on the Grey Ships).
Well, that's my best guesses or it.