I will share a couple of ideas with you regarding your request for proof that God exists, but I would encourage you to visit a Christian book store to see what they might have along these lines, and to talk to a pastor or counselor in a Bible-teaching church. With question such as this, you need someone to interact with and that’s too difficult with e-mail.
We really cannot prove that God exists as one would prove a scientific experiment, but we can point to tremendous evidence for the existence of God. Unfortunately, the impact of one of the strongest evidences, the creation, has been somewhat skewed by the hypothesis of evolution, a hypothesis which is fraught with problems, though these are swept under the rug by much of the scientific community.
The universe and all that is in it with the various complexities of say, just the human body, is an effect that requires an adequate cause, and the only sufficient cause is a sovereign God. For instance, the idea of evolution being an adequate cause falls apart on the grounds of the mathematical probabilities of a one cell organism evolving to the complexity of what is found in the creation today. Or take the uniqueness of the earth and life as we have it on the earth. The earth itself is evidence of design.
“If it were much smaller an atmosphere would be impossible (e.g. Mercury and the moon); if much larger the atmosphere would contain free hydrogen (e.g. Jupiter and Saturn). Its distance from the sun is correct—even a small change would make it too hot or too cold. Our moon, probably responsible for the continents and ocean basins, is unique in our solar system and seems to have originated in a way quite different from the other relatively much smaller moons. The tilt of the [earth’s] axis insures the seasons, and so on.” (Clark, R.E.D. Creation, London: Tyndale Press, p 10, quoted by Little, p. 11).
The uniqueness of the earth is evidence of design, not time plus chance. The Bible tells us,
1 The heavens declare the glory of God; the skies proclaim the work of his hands. 2 Day after day they pour forth speech; night after night they display knowledge. 3 There is no speech or language where their voice is not heard. 4 Their voice goes out into all the earth, their words to the ends of the world.
Further, Romans 1:18f teaches the principle, only it includes the warning that the real problem is man’s rebellion and refusal to accept the evidence of nature or creation.
18 The wrath of God is being revealed from heaven against all the godlessness and wickedness of men who suppress the truth by their wickedness, 19 since what may be known about God is plain to them, because God has made it plain to them. 20 For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that men are without excuse. 21 For although they knew God, they neither glorified him as God nor gave thanks to him, but their thinking became futile and their foolish hearts were darkened. 22 Although they claimed to be wise, they became fools 23 and exchanged the glory of the immortal God for images made to look like mortal man and birds and animals and reptiles.
In addition, there is the evidence of the many who have embraced the realities of God and Christianity and have experienced the power of Christ’s life in theirs as they embraced it in genuine faith and through the knowledge of the Bible. These include scientists, philosophers, and statesman, and many people who are highly intelligent.
But above all, one of the greatest evidences for the reality of God is the life, death, and resurrection of Jesus Christ. His resurrection, a historical fact backed up by tremendous historical evidence, proved Him to be the Son of God and Savior of men. This also, then, proves the reality of God, the truth of Scripture which He affirmed, and of man’s need of His life and death. Listen to the words of the Apostle Paul words spoken at Athens and recorded in the book of Acts in the New Testament.
22 Paul then stood up in the meeting of the Areopagus and said: “Men of Athens! I see that in every way you are very religious. 23 For as I walked around and looked carefully at your objects of worship, I even found an altar with this inscription: TO AN UNKNOWN GOD. Now what you worship as something unknown I am going to proclaim to you. 24 “The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands. 25 And he is not served by human hands, as if he needed anything, because he himself gives all men life and breath and everything else. 26 From one man he made every nation of men, that they should inhabit the whole earth; and he determined the times set for them and the exact places where they should live. 27 God did this so that men would seek him and perhaps reach out for him and find him, though he is not far from each one of us. 28 ‘For in him we live and move and have our being.’ As some of your own poets have said, ‘We are his offspring.’ 29 “Therefore since we are God’s offspring, we should not think that the divine being is like gold or silver or stone—an image made by man’s design and skill. 30 In the past God overlooked such ignorance, but now he commands all people everywhere to repent. 31 For he has set a day when he will judge the world with justice by the man he has appointed. He has given proof of this to all men by raising him from the dead.”
One book I would suggest is When Skeptics Ask by Geisler and Brooks (Victor Books). This book deals with questions about God and many other questions people often ask.