It is often claimed that, among the many cognitive flaws in ordinary human cognition, the confirmation bias is the most insidiously pro-religious. "You find what you're looking for" is a pithy way of debunking religious argumentation, since, presumably, a believer sets out with a notion of a good God and, lo and behold, finds evidence for Him... despite the actual evidence. Leaving aside the fact that this argument cuts both ways (viz., cognitive dissonance can be as falsely illuminating as it can be blinding), I would like to suggest that God, as the Good One, the very ground of all that Is, is found in a way akin to how we find beauty in our daily lives. As such, the confirmation-bias argument does not cut as much ice against theism as it might seem prima facie.
The older we get, the easier it is to find the world boring, which is largely why the older we get, the more boring we ourselves become. We've seen a thousand roses a thousand times, so there is no thrilling novelty in the next one we see. Likewise, especially with the expansion of "data absoprtion" via the Internet in our day, we have seen nearly everything, so nothing thrills us with its novelty. We suffer from epistemological gout. The world is so well known by us now that it is actually a very boring place for many people. This accounts, for instance, for the numerous cases of "Avatar blues" that befell viewers after seeing Avatar--and seeing how poorly our own all-too-mundane world compared to the primal beauty of the film. If we do not keep our eyes open, we will progressively lose sight of how beautiful the world really is. As Platonic thought has long held, Being is a (convertible) form of Beauty, both of which are (convertible) forms of Good. In a sense, all that Christianity adds to this worldview (aside from a rare respect for manual labor and a more 'terrestrial' anthropology) is a name for the Good ("God") and a face for the Beautiful (Christ manifest in the Eucharist).
The more a person seeks beauty in the world, the more she finds it. Why be ashamed to admit it? She must develop an "eye for beauty," as a wine taster and art critic must learn how to taste and how to see in ways the normal eye cannot appreciate. Here is a clear case of confirmation bias--I set out to find beauty and I find it!--yet I doubt this proves the unreality of beauty. If beauty is not falsified by aesthetic taste, why is God falsified by metaphysical wonder? "Objectively," nothing is beautiful, since objects do not behold anything. The 'objective' argument against theism is even less compelling, since God is not an 'object' in a world of differently sized objects. Rather, He is the very basis for there beings Objects, that is, entities subsistently beheld by a Subject. In any case, who says we live in a "purely objective" world? It is precisely by being committed to the value and enduring existence of beauty that the "metaphysical aesthete" discovers progressively more and stronger 'evidence' for the existence of beauty. So it is with God.
Let us be blunt, and biblical: He is seen by those who wish to see Him; He is present to those who admit and desire His presence. By contrast, He is as inscrutable and as boring to the secular eye as a Rembrandt painting might be to an infant. To argue against beauty on the grounds that those who see it "only see it because they choose to see it," is not to argue against beauty: it is rather to admit oneself cannot see the beautiful. Likewise, to argue against theism on the grounds that believers "find God because they want to," is not to argue against theism; it is simply to admit one's own lack of faith, one's poor vision in the world we inhabit.