I'm sure others will also respond in the next day or so, but I will try to compose a general argument tomorrow (after church of course) on the existence of God. For now, I'll just relay a quote from the famous anti-Christian Carl Sagan: "Absence of evidence is not evidence of absence". He said this in response to the question of the existence of UFOs, but it applies equally well to any other theoretical idea which can neither be proved nor disproved.
You've probably already guessed that I'm one of the "theoreticians" around here. I'll be approaching the issue from a position of logic and conventional Science as much as possible. I'm no expert, but hey, I'm sure you didn't come here to find one of those anyway! Hope we can have a nice discussion.