JOEL - People who have it set in their minds that the Book of Mormon is nothing but fiction, are going to be hard to convince otherwise, unless you can get them to actually read the book and let it do the convincing for itself. I can give you a list of Bible scriptures that apply to the Book of Mormon, but they are better used only to give support to an already existing testimony of it.
Here they are:

1. In Jacob's blessing to Joseph, a promise was given that he would become a fruitful bough whose "branches" would run "over the wall" and that his posterity would be heir to divine blessings (Gen. 49:22-26). A verse in the Book of Mormon explains that this branch is the Nephites who were decendents of Joseph:
"Hear ye the words of the prophet, ye who are a remnant of the house of Israel, a branch who have been broken off; (1 Ne. 19:24)
Running over the wall refers to Lehi's journey with his family across the ocean to the American continent.

2. A prophesy in Ezekiel explains:
"The word of the LORD came again unto me, saying,
Moreover, thou son of man, take thee one stick, and write upon it, For Judah, and for the children of Israel his companions: then take another stick, and write upon it, For Joseph, the stick of Ephraim, and for all the house of Israel his companions:
And join them one to another into one stick; and they shall become one in thine hand." (Ezek. 37:15-19)
The stick of Judah represents the Bible and the stick of Joseph represents the Book of Mormon.
This is further explained by Nephi :
"Wherefore, the fruit of thy loins shall write; and the fruit of the loins of Judah shall write; and that which shall be written by the fruit of thy loins, and also that which shall be written by the fruit of the loins of Judah, shall grow together, unto the confounding of false doctrines and laying down of contentions, and establishing peace among the fruit of thy loins, and bringing them to the knowledge of their fathers in the latter days, and also to the knowledge of my covenants, saith the Lord." (2 Nephi 3:12)
Together in one hand they both testify of Christ and bring to all the knowledge of the forefathers and the covenants.

3. Isaiah and Nephi explained that the voice of Joseph's descendants would be heard again as a voice "out of the ground"; their speech would "whisper out of the dust":
"And thou shalt be brought down, and shalt speak out of the ground, and thy speech shall be low out of the dust, and thy voice shall be, as of one that hath a familiar spirit, out of the ground, and thy speech shall whisper out of the dust."(Isaiah 29:4)
The Gold plates came out of the ground and the translation of it, known as the Book of Mormon, has a familiar voice, or in other words a style of speech like the Bible that people would recognize. (See 2 Ne. 33:13)

4. A part of the gold plates were sealed when Joseph Smith received them. Isaiah spoke of "the words of a book that is sealed" that would be delivered to a "learned" person.
"And the vision of all is become unto you as the words of a book that is sealed, which men deliver to one that is learned, saying, Read this, I pray thee: and he saith, I cannot; for it is sealed:
And the book is delivered to him that is not learned, saying, Read this, I pray thee: and he saith, I am not learned.
Wherefore the Lord said, Forasmuch as this people draw near me with their mouth, and with their lips do honour me, but have removed their heart far from me, and their fear toward me is taught by the precept of men:
Therefore, behold, I will proceed to do a marvellous work among this people, even a marvellous work and a wonder: for the wisdom of their wise men shall perish, and the understanding of their prudent men shall be hid.(Isa. 29:11-14)
The "book that is sealed" are the Gold plates. The learned person was Professor Charles Anthon, who when given a copy of some of the writings, authenticated the translation. When later told where the writings came from he said, "I can not read a sealed book"(verse 11).
The one who was not learned was Joseph Smith(verse 12). The marvelous work and wonder that was performed was the bringing forth of the Book of Mormon and restoration of the Gospel(verse 14).

5. Jesus told His followers in Palestine:
"And other sheep I have, which are not of this fold: them also I must bring, and they shall hear my voice; and there shall be one fold, and one shepherd."(John 10:16)
Who were these other sheep? When Jesus appeared on the American continent He specifically refered to these words recorded in John when He said:
"And verily I say unto you, that ye are they of whom I said: Other sheep I have which are not of this fold; them also I must bring, and they shall hear my voice; and there shall be one fold, and one shepherd." (3 Nephi 15:21)
He taught them His gospel and set up His church there so that they could be in the one fold with those on the Eastern continent, and Christ could be the Shepherd of them all.

6. John forsees the appearance of the angel Moroni to Joseph Smith in his revelation:
"And I saw another angel fly in the midst of heaven, having the everlasting gospel to preach unto them that dwell on the earth, and to every nation, and kindred, and tongue, and people," (Rev. 14:6)
Missionaries of our church now carry that everlasting gospel, contained in the Book of Mormon "to every nation, and kindred, and tongue, and people".

7. The scriptures tell us:
"In the mouth of two or three witnesses shall every word be established." (2 Cor. 13:1, Matt 18:16)
For hundreds of years the Bible was the only witness of Jesus Christ. With the Book of Mormon we now have the two required witnesses.