Leah has written less than one might hope on her reasons for converting, and basically nothing on how she now deals with all the usual atheist objections to Christian belief. Her primary reason for conversion appears to have been that Christianity fits better than atheism with the moral system she has always found most believable.
Someone who I think is an LW participant (but I don't know for sure, and I don't know under what name) wrote this fairly lengthy apologia for atheism; I think it was a sort of open letter to his friends and family explaining why he was leaving Christianity.
In the course of my own transition from Christianity to atheism I wrote up a lot of notes (approximately as many words as one paperback book), attempting to investigate the issue as open-mindedly as I could. (When I started writing them I was a Christian; when I stopped I was an atheist.) I intermittently think I should put them up on the web, but so far haven't done so.
There are any number of books looking more or less rigorously at questions like "does a god exist?" and "is Christianity right?". In just about every case, the author(s) take a quite definite position and are writing to persuade more than to explore, so they tend not to be, nor to feel, unbiased. Graham Oppy's "Arguing about gods" is pretty even-handed, but quite technical. J L Mackie's "The miracle of theism" is definitely arguing on the atheist side but generally very fair to the other guys, and shows what I think is a good tradeoff between rigour and approachability -- but it's rather old and doesn't address a number of the arguments that one now hears all the time when Christians and atheists argue. The "Blackwell Companion to Natural Theology" is a handy collection of Christians' arguments for the existence of God (and in some cases for more than that); not at all unbiased but its authors are at least generally trying to make sound arguments rather than just to sound persuasive.
I suggest that a primary cause of confusion about the distinction between "belief", "truth", and "reality" is qualitative thinking about beliefs.
Consider the archetypal postmodernist attempt to be clever:
No, different societies have different beliefs. Belief is of a different type than truth; it's like comparing apples and probabilities.
No, these sentences mean quite different things, which is how I can conceive of the possibility that my beliefs are false.
And that's what I mean by putting my finger on qualitative reasoning as the source of the problem. The dichotomy between belief and disbelief, being binary, is confusingly similar to the dichotomy between truth and untruth.
So let's use quantitative reasoning instead. Suppose that I assign a 70% probability to the proposition that snow is white. It follows that I think there's around a 70% chance that the sentence "snow is white" will turn out to be true. If the sentence "snow is white" is true, is my 70% probability assignment to the proposition, also "true"? Well, it's more true than it would have been if I'd assigned 60% probability, but not so true as if I'd assigned 80% probability.
When talking about the correspondence between a probability assignment and reality, a better word than "truth" would be "accuracy". "Accuracy" sounds more quantitative, like an archer shooting an arrow: how close did your probability assignment strike to the center of the target?
To make a long story short, it turns out that there's a very natural way of scoring the accuracy of a probability assignment, as compared to reality: just take the logarithm of the probability assigned to the real state of affairs.
So if snow is white, my belief "70%: 'snow is white'" will score -0.51 bits: Log2(0.7) = -0.51.
But what if snow is not white, as I have conceded a 30% probability is the case? If "snow is white" is false, my belief "30% probability: 'snow is not white'" will score -1.73 bits. Note that -1.73 < -0.51, so I have done worse.
About how accurate do I think my own beliefs are? Well, my expectation over the score is 70% * -0.51 + 30% * -1.73 = -0.88 bits. If snow is white, then my beliefs will be more accurate than I expected; and if snow is not white, my beliefs will be less accurate than I expected; but in neither case will my belief be exactly as accurate as I expected on average.
All this should not be confused with the statement "I assign 70% credence that 'snow is white'." I may well believe that proposition with probability ~1—be quite certain that this is in fact my belief. If so I'll expect my meta-belief "~1: 'I assign 70% credence that "snow is white"'" to score ~0 bits of accuracy, which is as good as it gets.
Just because I am uncertain about snow, does not mean I am uncertain about my quoted probabilistic beliefs. Snow is out there, my beliefs are inside me. I may be a great deal less uncertain about how uncertain I am about snow, than I am uncertain about snow. (Though beliefs about beliefs are not always accurate.)
Contrast this probabilistic situation to the qualitative reasoning where I just believe that snow is white, and believe that I believe that snow is white, and believe "'snow is white' is true", and believe "my belief '"snow is white" is true' is correct", etc. Since all the quantities involved are 1, it's easy to mix them up.
Yet the nice distinctions of quantitative reasoning will be short-circuited if you start thinking "'"snow is white" with 70% probability' is true", which is a type error. It is a true fact about you, that you believe "70% probability: 'snow is white'"; but that does not mean the probability assignment itself can possibly be "true". The belief scores either -0.51 bits or -1.73 bits of accuracy, depending on the actual state of reality.
The cognoscenti will recognize "'"snow is white" with 70% probability' is true" as the mistake of thinking that probabilities are inherent properties of things.
From the inside, our beliefs about the world look like the world, and our beliefs about our beliefs look like beliefs. When you see the world, you are experiencing a belief from the inside. When you notice yourself believing something, you are experiencing a belief about belief from the inside. So if your internal representations of belief, and belief about belief, are dissimilar, then you are less likely to mix them up and commit the Mind Projection Fallacy—I hope.
When you think in probabilities, your beliefs, and your beliefs about your beliefs, will hopefully not be represented similarly enough that you mix up belief and accuracy, or mix up accuracy and reality. When you think in probabilities about the world, your beliefs will be represented with probabilities ∈ (0, 1). Unlike the truth-values of propositions, which are in {true, false}. As for the accuracy of your probabilistic belief, you can represent that in the range (-∞, 0). Your probabilities about your beliefs will typically be extreme. And things themselves—why, they're just red, or blue, or weighing 20 pounds, or whatever.
Thus we will be less likely, perhaps, to mix up the map with the territory.
This type distinction may also help us remember that uncertainty is a state of mind. A coin is not inherently 50% uncertain of which way it will land. The coin is not a belief processor, and does not have partial information about itself. In qualitative reasoning you can create a belief that corresponds very straightforwardly to the coin, like "The coin will land heads". This belief will be true or false depending on the coin, and there will be a transparent implication from the truth or falsity of the belief, to the facing side of the coin.
But even under qualitative reasoning, to say that the coin itself is "true" or "false" would be a severe type error. The coin is not a belief, it is a coin. The territory is not the map.
If a coin cannot be true or false, how much less can it assign a 50% probability to itself?