Prominent disbelievers in Christianity today - Richard Dawkins, Daniel Dennett, Sam Harris, and Christopher Hitchens - insist that sufficient reasons do not exist for the existence of God, and you are obviously in that camp. Dawkins, for example, says that the claim of God's existence is a scientific hypothesis that should be open to rational demonstration. He and his co-skeptics want a logical or empirical argument for God that is airtight and therefore convinces almost everyone. They, like you, and many on these forums, won't believe in God until they get it.
Is there anything wrong with that? I think so. These authors are evaluating Christian arguments by what some have called "strong rationalism". Its proponents laid down what was called the 'verification principle", namely, that no one should believe a proposition unless it can be proved rationally by logic or empirically by sense experience (which is what you are asking for, right?). What is meant by the word "proved"? Proof, in this view, is an argument so strong that no person whose logical faculties are operating properly would have any reason for disbelieving it. Atheists and agnostics ask for this kind of "proof" for God, but are not alone in holding to strong rationalism. You tend to believe that many Christians claim that their arguments for faith are so strong that all who reject them are simply closing their minds to the truth out of fear or stubbornness.
Despite all the books calling Christians to provide proofs for their beliefs, you won't see philosophers doing so, not even the most atheistic. The great majority think that strong rationalism is nearly impossible to defend. To begin with, it can't live up to it's own standards. How could you empirically prove that no one should believe something without empirical proof? You can't, and that reveals it to be, ultimately, a belief. Strong rationalism also assumes that it is impossible to achieve "the view from nowhere", a position of almost complete objectivity, but virtually all philosophers today agree that is impossible. We come to every individual evaluation will all sorts of experiences and background beliefs that strongly influence our thinking and the way our reason works. It is not fair, then, to demand argument that all rational people would have to bow to.
Basically, it comes down to this. In Is there a God? Oxford philosopher Richard Swinburne argues powerfully that belief in God can be tested and justified (but not proven). The view that there is a God, he says, leads us to expect the things that we observe - that there is a universe at all, that scientific laws operate within it, that it contains human beings with consciousness and with indelible moral sense. The theory that there is no God, he argues, does not lead us to expect any of these things. Therefore, belief in God offers a better empirical fit, it explains and accounts for what we see better than the alternative account of things. No view of God can be proven, but that does not mean that we cannot sift and weigh the grounds for various religious beliefs that some or even one is the most reasonable.
But, I digress. According to you, I'm just a dumb Christian.
