"I'm not going to believe in some 3,000 year old book," quips the atheist. No matter how many times you quote "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 people are without excuse," (Romans 1:20), he's still like the neighborhood bully pulling around his dog Spike whose collar bears his namesake: "Gimme yer lunch munny er Ah'll ter yer heart out." He doesn't want to be told that he has to get his own lunch money from Ma 'n Pa himself, and thankfully one of the lil'uns' big brother shows up. Sock it to 'im: suck a knuckle sandwhich!
The "New Atheists" have been around for almost a decade now, not bothering to actually think about things reasonably, intelligently, and logically, like their forebears in the philosophy departments around the globe (now diminishing thanks a good deal to the work of Plantinga, Wolterstorff, and others). So often I've heard (or read) some of the belligerent ilk of this kind, it reminds me very much of dealing with Christian fundamentalists who insist on Rapture Theology as a test of orthodoxy (something I used to do myself, sadly), or like those guys who want to argue about who the Nephilim were (Genesis 6:1-4).
If you must respond to the bully atheist at whatever party, tailgate, or campus square you're at, you can do yourself a favor by pulling a Billy Martin dust kick (I'm pretty sure Mr. Martin picked this up from the Lord [Matthew 10:14]). Or, if you're OCD for apologetics and "just havta win this one," you can ask the ranting cacophony of the latest, trendy, noise-whirler if his words have any lasting meaning or significance. If they do, then that means there is meaning in texts and sayings that are supra-temporal, lasting for ages and time everlasting. If his words don't have any lasting authority, then you can ask him why you should believe someone who doesn't have anything profound to say?
The typical move is the punt to "Science," the stone god of the new atheism, which is really logical positivism at best or crude empiricism at worst. But this only pushes the question back further toward the black hole of what "science" is, and how things can be known. The next move by our space traveler will be an appeal to the senses (empiricism). But here comes the black hole over which hangs the sign, "Abandon all hope, ye who enter here": how do we justify that we should trust our senses? After all, what keeps someone from being a radical skeptic about the nature of reality? And where is it written that we should "obey" the law that we "ought" (an ethical ought) to trust our senses?
Of course, we should trust our senses, but justifying their use both ethically and epistemologically is a task that the atheist is hard-pressed to prove given his naturalism, as normativity is blown out the door and relativism ensues. And when the new atheist says we have to trust our senses because they work, then he's reasoning in a circle as well as resorting to pragmatism. Getting him to believe this however will require another cup of something, and a good dose of humility. But I'm afraid we've passed that point with these people.
So, Christian, you are free to believe in a 3,000 year old book that bespeaks of God's creative power and governance over his creation. One of the reasons for your confidence in this is because words have lasting significance and meaning no matter when they are said or written. Don't be intimidated by folks who want to tell you that believing the words of a book, just because it is old, is irrational. For when skeptics hurl the heads they've chopped off in the field of battle from their catapult, they chopping off their own heads, not yours.