How will they find out (about Jesus)?

One of the questions brought up by unbelievers is 'How is Christianity true if someone out in the middle of nowhere has never heard of Jesus is condemned to an eternal hell when they die?"  This is a fair question.  Usually the well meaning will answer something like "what does it matter to you, you have heard so what will you do with Jesus".  This is not what they asked.  They asked an honest question on about how a just God can condemn someone that has not had the opportunity to know about Jesus.  This is a question about Yahweh's omnipresence and His concern with the unsaved.  If someone has no opportunity to believe and be saved, it puts into question of who God is in the unbelievers' mind.

We are to send out missionaries and to witness to the lost throughout the world.  There is no question that this is the Great Commission Yeshua gave His followers.  There are still those who have not had the opportunity to hear about Yeshua.  Scripture is clear that the Creation testifies that there is a God.

Romans 1:20  For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead; so that they are without excuse:

Scripture also shows that those who have more knowledge are responsible for that knowledge.  Those with less knowledge will be held accountable, and punished,  for what they did know :

Luke 12
46  The lord of that servant will come in a day when he looketh not for him, and at an hour when he is not aware, and will cut him in sunder, and will appoint him his portion with the unbelievers.
47  And that servant, which knew his lord's will, and prepared not himself, neither did according to his will, shall be beaten with many stripes.
48  But he that knew not, and did commit things worthy of stripes, shall be beaten with few stripes. For unto whomsoever much is given, of him shall be much required: and to whom men have committed much, of him they will ask the more.

When someone is truly seeking Truth, they will be shown the truth regardless of whether or not there is anyone around to tell them.  Yeshua said even the rocks will cry out :

Luke 19
39  And some of the Pharisees from among the multitude said unto him, Master, rebuke thy disciples.
40  And he answered and said unto them, I tell you that, if these should hold their peace, the stones would immediately cry out.

In the bible, there was a eunuch that was seeking truth and he did not understand.  Yahweh provided him someone to show him the truth and the very same thing happens today:  a believer being placed in the life of an unbeliever that is searching for the truth:

Acts 8
26  And the angel of the Lord spake unto Philip, saying, Arise, and go toward the south unto the way that goeth down from Jerusalem unto Gaza, which is desert.
27  And he arose and went: and, behold, a man of Ethiopia, an eunuch of great authority under Candace queen of the Ethiopians, who had the charge of all her treasure, and had come to Jerusalem for to worship,
28  Was returning, and sitting in his chariot read Esaias the prophet.
29  Then the Spirit said unto Philip, Go near, and join thyself to this chariot.
30  And Philip ran thither to him, and heard him read the prophet Esaias, and said, Understandest thou what thou readest?
31  And he said, How can I, except some man should guide me? And he desired Philip that he would come up and sit with him.
32  The place of the scripture which he read was this, He was led as a sheep to the slaughter; and like a lamb dumb before his shearer, so opened he not his mouth:
33  In his humiliation his judgment was taken away: and who shall declare his generation? for his life is taken from the earth.
34  And the eunuch answered Philip, and said, I pray thee, of whom speaketh the prophet this? of himself, or of some other man?
35  Then Philip opened his mouth, and began at the same scripture, and preached unto him Jesus.
36  And as they went on their way, they came unto a certain water: and the eunuch said, See, here is water; what doth hinder me to be baptized?
37  And Philip said, If thou believest with all thine heart, thou mayest. And he answered and said, I believe that Jesus Christ is the Son of God.
38  And he commanded the chariot to stand still: and they went down both into the water, both Philip and the eunuch; and he baptized him.
39  And when they were come up out of the water, the Spirit of the Lord caught away Philip, that the eunuch saw him no more: and he went on his way rejoicing.

The apostle Paul was given a vision of Yeshua and came to faith when Yeshua showed him that He is the Messiah:

Acts 22
3  I am verily a man which am a Jew, born in Tarsus, a city in Cilicia, yet brought up in this city at the feet of Gamaliel, and taught according to the perfect manner of the law of the fathers, and was zealous toward God, as ye all are this day.
4  And I persecuted this way unto the death, binding and delivering into prisons both men and women.
5  As also the high priest doth bear me witness, and all the estate of the elders: from whom also I received letters unto the brethren, and went to Damascus, to bring them which were there bound unto Jerusalem, for to be punished.
6  And it came to pass, that, as I made my journey, and was come nigh unto Damascus about noon, suddenly there shone from heaven a great light round about me.
7  And I fell unto the ground, and heard a voice saying unto me, Saul, Saul, why persecutest thou me?
8  And I answered, Who art thou, Lord? And he said unto me, I am Jesus of Nazareth, whom thou persecutest.
9  And they that were with me saw indeed the light, and were afraid; but they heard not the voice of him that spake to me.
10  And I said, What shall I do, Lord? And the Lord said unto me, Arise, and go into Damascus; and there it shall be told thee of all things which are appointed for thee to do.
11  And when I could not see for the glory of that light, being led by the hand of them that were with me, I came into Damascus.
12  And one Ananias, a devout man according to the law, having a good report of all the Jews which dwelt there,
13  Came unto me, and stood, and said unto me, Brother Saul, receive thy sight. And the same hour I looked up upon him.
14  And he said, The God of our fathers hath chosen thee, that thou shouldest know his will, and see that Just One, and shouldest hear the voice of his mouth.
15  For thou shalt be his witness unto all men of what thou hast seen and heard.
16  And now why tarriest thou? arise, and be baptized, and wash away thy sins, calling on the name of the Lord.

Next, their is NUMEROUS testimonies of those, especially former muslims and Jewish people, that are being given dreams and visions of

Yeshua (Jesus) and are coming to faith either by Yeshua showing them the truth directly or they being so bothered by their dreams they seek out the truth from a Christian.

http://morethandreams.org/

“More Than Dreams” tells the compelling, true stories of five Muslims from five countries who share one life-changing experience. Each of

them saw Jesus Christ in a dream or a vision and their lives were forever transformed.

http://www.beliefnet.com/columnists/watchwomanonthewall/2013/02/jesus-appears-to-muslims-in-dreams-conversions-and-testimonies-video.html

“Great things are happening in the Muslim world,” Doyle said in an email to WND. “It’s all very unexpected.”

Doyle told WND that he is familiar with Farraj’s program and that Jesus is breaking through where missionaries have not succeeded.

“We’ve been seeing this for 15 years now, where Muslims are no longer Muslims but are Jesus followers,” Doyle said. “It’s someone who is a Christian, someone who is willing to die for Jesus.

“It all started with them with a dream,” Doyle said. “They had a Jesus dream, and some of them had many Jesus dreams. They would seek out Christians after a while because the dreams would get so intense that they wanted an answer.”

http://www.the-new-way.org/testimonies/conv_giud_03_the_man_in_white_robe.html

The dream repeated itself night after night. I became worried and nervous. I finally consulted a doctor out of fear that I might be losing my mind. He prescribed medication to relax me. I also inquired of a Christian friend, "What could this dream mean?" She replied, "You have described Jesus and your dream is showing how Jesus saves those who believe him."

If someone is sincerely seeking Truth, Yahweh WILL show them truth even if there does not seem to be a way.