Attempts to validate the historicity of the Bible are, in a sense, pointless. The sense I refer to is in which someone would use the Bible's historicity to prove the Christian religion. The following is an example using the Bible's reliability in particular, but the core principle is definitely a lesson to be remembered at all times.
"The historical evidence for the accuracy of our Bible manuscripts is just as strong as the historical evidence for countless other texts we accept as accurate." This claim is made all the time by Christians. I am not a Biblical historian, so this claim may very well be accurate (although there is much debate on the subject). The point is, however, that this really does not matter in terms of proving the claims of Christianity. Whether or not the original writers of the Gospels were misquoted does not matter. We could know word for word what they wrote, and we would still be left with the word of four anonymous individuals writing some 40-50 years after Jesus' ministry.
"But we just have hearsay testimony of countless other historical documents, and we trust their accuracy!" I am always surprised that I really need to point out the difference between the Bible and other historical documents. All claims made in history books that we currently accept as accurate are not "extraordinary" claims. The assertions they make are compatible with the body of knowledge (historical and otherwise) that we as a species have amassed up to this point. When we examine a claim, we determine its likelihood based not only on the strength of the evidence in favor of the claim, but also the evidence against it, which is all our previously confirmed knowledge that contradicts or excessively complicates this claim. I'll provide an analogy, because that has sort of become my thing:
If I receive a text message from my friend which reads "I just found twenty dollars on the sidewalk", I will be most likely to believe him. Why? Because money is occasionally dropped and I have heard of this happening many times before (and confirmed it). I have no knowledge that suggests my friend would not have been fortunate today. Now, imagine I receive a text message from my friend that instead says "My cat has begun to levitate and speak English fluently." My first thought might be that he is pulling my leg, or perhaps a friend of his has taken his phone and is trying to get funny responses from me. I certainly would not immediately conclude that simply because I have the same evidence that I do for the previous message (my friend's word), then the most likely explanation is that his cat is truly levitating and conversing with him. We must balance claims against what we have already inferred about the universe.
Just for fun, let's examine the claims of the Bible. It claims that there is an entirely separate plane of existence, independent of all things natural. It claims that there is a being who created and supervises existence as we know it. It claims that this being has total and absolute power over this universe, and that this being repeatedly stood the laws of physics on their head a few thousand years ago, performing acts that included but were not limited to parting an ocean, impregnating a virgin, raising people from the dead, turning a woman to salt, committing various acts of genocide, and commandeering a horde of bears to tear apart some children who made fun of Elisha's bald head.
I assert that, if this had been documented by hundreds of independent contemporary sources, and we had the original manuscripts, and the manuscripts were all dated between 30 and 33 C.E., we would not have enough "evidence" to back up such ridiculous claims. To validate these nonsensical, incoherent demonstrations of verbal and intellectual chaos, each and every separate claim would have to be cross-checked, tested, documented, taped, debated, and generally examined for at least a century and a half.
That's a hypothetical minimum, by the way; that exact amount of effort hasn't managed to convince creationists of evolution yet.