Lets see...Sauron was huge(about the size of a Primarch) when he was alive(?) then became a huge burning eye (Ocularis Terribus) had 9 corrupted(Warped?) once-human Nazgul minions (terror specialists...Night Lords?), attacked the empire of men(Imperium) and the elves(Eldar) while the dwarves seemed to be non-existant(Squats)..

No similarity to 40K what so ever.

Well, according to the book, the dwarves of the Lonely Mountain came to the aid of Laketown against the forces of Sauron during the War of the Ring. But, all in all, the numbers of dwarves weren't as significant in the contested areas (the known dwarven realms besides Lonely Mountain at the end of the Third Age were based in Ered Luin, the Blue Mountains near the Shire and the Iron Hills to the north of the Lonely Mountain). It is also unknown how many dwarves remained there after the Lonely Mountain's establishment, and the dwarves from the latter would probably come to the aid of their brethren in the battle if they had time. So they weren't "non-existant", but, yeah, they didn't play much of a significant role in the War (so didn't elves, though).

And you just made the understanding of 40k a lot more easier for me...

LOL I was mostly being facetious but all in fun,

Like all epic stories there are some shared formulae, Tolkien himself borrowed many of these formulae from the ancient ballads/sagas when he created his masterworks,

Like all good war stories 40K is about good(?) vs evil(?), sacrifice, loyalty, betrayal, blood, misery, death, loss and glory....and dozens of other emotive subjects thrown together.

I used to tabletop when I was a younger but I havnt for over a decade now, I'm still very invested in this universe through the Black Libraries fiction.

Welcome to the universe of Warhammer 40K, may your stay be as enjoyable and rewarding for you as it has for so many of us.

Sorry, I just like when things are as accurate as possible.

But yeah, this kind of analogy was quite helpful. Thanks ^^