This is not a serious story. I know almost nothing about the Valar, and really not that much about Middle Earth in general, and most of this is just... meant to be a little bit self indulgent and cliche. So I'm gonna skim the parts I don't know too much about, which will be... a lot. I just wanted to write an Elfling!Harry story where Harry was an elfling before he came to Hogwarts, rather than after. But if there's anything egregious I should fix, feel free to tell me. Spots that I'm basically guessing at and are probably terribly wrong are marked by a *. Sorry.
Part of this is old, and I'm not sure where I got a lot of the Elvish names from. I believe I made a couple of them up wholesale, so they may or may not be meaningless. Other notes: I initially planned that Harry would land during the crisis of the Ring and such, but didn't like how that was working when I made the beginning more plausible, so I changed it. But I kept a lot of the writing, so if something seems not quite right, that's probably why.
Oh: and on elf aging? I'm, again, uncertain if this matches any of the canon at all, but I decided that elves age four times slower than humans. *Note: I changed this back from 62 years because that made it seem inappropriate that Harry was still a kid.
His mother fell to the floor. Harry glared hatefully at the man with the red eyes. He made his mother fall down, and he was mean, and Harry wanted him to go away more than he'd ever wanted anything else in his young life. He had made Mummy make a mean noise and he was mean and Harry didn't like him and he shouldn't be here.
Voldemort, meanwhile, smirked down at the child they said would be his undoing and lazily cast, "Avada Kedavra." Not such a threat after all. The prophecy, clearly, was only a fakery by a half-baked seer who didn't know what she was saying. Soon, he would truly be invincible; he would seize Great Britain and then the rest of the world. He was unkillable!
The spells, one invisible and chaotic, and the other an evil, focused green, met in midair and ricocheted. The air pulsed with the magic of Lily's sacrifice. At exactly the same moment, the two spells hit their castors and the world lit up.
Harry's desire for the bad man to go away and Lily's desperation that her son be safe gave the resulting pulse of magic energy and direction; the momentary gap in the world as Voldemort's soul soared into the space between life and death gave it a place to go. With a roar reminiscent of a jet engine and a flash brighter than the sun, Harry Potter, bawling and bleeding, disappeared.
~_!_*_!_~
A strange child sat outside the gates of the world, crying. The Valar gathered, uncertain and confused.
They could read his fate clearly; he was a child of destiny, meant for great and terrible deeds in his own world. They would not meddle in the fates of other worlds: for all their power within Arda, the Valar did not like to step outside their realm. Harry Potter's place was far away from Middle Earth.
And yet the Valar were not unkind, and the boy was right outside their gates. Besides the difficulty of sending him back at all, surely, if that Earth's fate had relied so much upon the boy, he would have remained. Surely they could give him the peace and comfort of Middle Earth for a little while, since fate, though it could never be stopped, might often be delayed.
And so the Valar took the boy in and made him one of their own. He would have a chance to be a happy child in Greenwood, a chance his original world would have denied him. He would live in Arda until Fate called to him once more.
~_!_!_!_~
Wizards were celebrating in pubs all over Britain; owls filled the skies and strange revelers the streets. Albus Dumbledore had not joined them. He remained in his office, staring with focused intent on a strange, spinning device.
Wizards and witches the world over were gossiping about Harry Potter's disappearance and toasting the family's sacrifice. Already, decorative products were emblazoned with The-Boy-Who-Disappeared, and most assumed he had died: vaporized, perhaps, or zapped into nonexistence.
Albus Dumbledore had not joined the gossipers, either.
The strange device creakily and unsteadily made a slow revolution, as it had every five minutes since Harry had disappeared.
Harry Potter was out there somewhere. Harry Potter had survived.