JOEL - The only story I have heard of is a report from Brigham Young, who tells how Joseph Smith and Oliver Cowdery returned the gold plates to a cave in the hill Cumorah that had a large room containing many plates.

"I believe I will take the liberty to tell you of another circumstance that will be as marvelous as anything can be. This is an incident in the life of Oliver Cowdery, but he did not take the liberty of telling such things in meeting as I take. I tell these things to you, and I have a motive for doing so. I want to carry them to the ears of my brethren and sisters, and to the children also, that they may grow to an understanding of some things that seem to be entirely hidden from the human family. Oliver Cowdery went with the Prophet Joseph when he deposited these plates. Joseph did not translate all of the plates; there was a portion of them sealed, which you can learn from the Book of Doctrine and Covenants. When Joseph got the plates, the angel instructed him to carry them back to the hill Cumorah, which he did. Oliver says that when Joseph and Oliver went there, the hill opened, and they walked into a cave, in which there was a large and spacious room. He says he did not think, at the time, whether they had the light of the sun or artificial light; but that it was just as light as day. They laid the plates on a table; it was a large table that stood in the room. Under this table there was a pile of plates as much as two feet high, and thee were altogether in this room more plates than probably many wagon loads; they were piled up in the corners and along the walls.
The first time they went there the sword of Laban hung upon the wall; but when they went again it had been taken down and laid upon the table across the gold plates; it was unsheathed, and on it was written these words: "This sword will never be sheathed again until The Kingdoms of this world become the Kingdom of our God and his Christ"' (Journal of Discourses, 19:36-39)

Heber C. Kimball refered to this same experience:

"How does it compare with the vision that Joseph and others had, when they went into a cave in the hill Cumorah and saw more records than ten men could carry? There were books piled up on tables, book upon book. Those records this people will yet have, if they accept of the Book of Mormon and observe its precepts , and keep the commandments." (Journal of Discourses, 4:105)

I do not know how accurate this story is. We do know from the Book of Mormon text that there were many plates that Mormon used to write the smaller set of plates that were given to Joseph Smith. These records were kept hidden in a hill called Cumorah.

"And it came to pass that when we had gathered in all our people in one to the land of Cumorah, behold I, Mormon, began to be old; and knowing it to be the last struggle of my people, and having been commanded of the Lord that I should not suffer the records which had been handed down by our fathers, which were sacred, to fall into the hands of the Lamanites, (for the Lamanites would destroy them) therefore I made this record out of the plates of Nephi, and hid up in the hill Cumorah all the records which had been entrusted to me by the hand of the Lord, save it were these few plates which I gave unto my son Moroni."(Mormon 6:6)

The "few plates" Mormon gave Moroni were the same ones given to Joseph Smith. So apparently there is a hill somewhere that Mormon called Cumorah where all the original records might be hidden.
Joseph Smith said the Angel Moroni has them in his posession now:

"When according to arrangements, the messenger called for them, I delivered them up to him; and he has them in his charge until this day, being the second day of May, one thousand eight hundred and thirty-eight." (Joseph Smith History 1:60)

So the Angel Moroni has them but we don't really know where he is keeping them. They may be in the Hill Cumorah or somewhere else, but there have been no serious attempts to find them. I doubt that God will allow it.