Alright, so they're all the typical girl falls into Middle Earth stories that I can stand.

The Hematic is a story I'm still following and it's fantastic hands down best of my recs, it's set in the Second Age though. It's a bit unfamiliar if you haven't read Silmarillion though I haven't and can still follow along pretty well. The Hematic is engaging sort of a horror/thriller it has a grim but one of the most unique ways I've ever seen an SI enter into fanfiction. The main character is kind of messed up but you can sort of sympathize with her. My favourite character is surprisingly, Lucy the main character even though usually [/spoiler] Glorfindel the crazy awesome balrog killer though in this it's unlikely he'll be killing any balrogs [/spoiler] would be. A horror drama story that I genuinely want to keep slogging through is pretty rare for me but thiss is a story that deserves the praise.
link https://www.fanfiction.net/s/10282151/1/The-Hematic

I read this a while ago but I remember it being pretty solid and I loved the twist it's completed and has a sequel, to be honest a bit generic as there are a few later Realistic girl falls into middle earth that are written better but this was the first of it's type
https://www.fanfiction.net/s/1690622/1/Don-t-Panic
Oh and the plot twist I really liked was in the sequel

Lastly for now though I remember a few better but these are the first that pop up
This was memorable in how it had some creative ideas it didn't have much plot though.
https://www.fanfiction.net/s/8836050/1/The-Skipper

 

I recall this one being fairly solid:

Home with the Fairies by I-Mushi
We've all seen the horribly butchered and cliché girl-falls-into-Middle-Earth stories. So is it possible to make a semi-realistic one? Follow Maddie on her own adventure exploring Middle Earth as the opposite of a Tenth Walker. COMPLETE


Chapters: 30 - Words: 255,903

https://www.fanfiction.net/s/6024634/1/Home-with-the-Fairies

 

There is one really old HP in LOTR story that is not as good as SoA but still pretty good.

Harry comes to middle earth by dragonballs(?) or something like that, he settles down to Rivendell long before Istari comes and when they do they call him the black wizard because how often he disagrees with Saruman.

Its name eludes me at the moment tough. IT was really old. It is in that archive thingy DLP has tough. You know the one you can download. So theorically it should be in the Alternates section of this forum.

Edit: Ayup
https://forums.darklordpotter.net/showthread.php?t=1570

 

There's one I remember with Wolverine dumped into middle-earth, and for some reason he goes along with the fellowship. I think it's this one - It's an odd coincidence, but I'm not entirely sure. It wasn't great, and was essentially "Lord of the Rings, but Wolverine is there too!", but it could've been worse.

Spoiler

I remember Wolverine goes back to New York at the end of the story, along with his elf wife, Aragorn, and Arwen.

There's also Hear Me Roar, where the whole of the Lannister lands gets transplanted into Middle Earth. There's a few issues, but it was good enough to get into the library.

Don't have any SI/OC ones though, I'm afraid.

 

I read that last night. It's really terrible even for a 2006 fic if you ask me.

 

Then please post it on the review board.