Hi! I stumbled upon your web page by accident, at which point it just sucked me in for several days. It's great!

Having said this, I find I must disagree with something you say in http://www.abarnett.demon.co.uk/atheism/creation.html , namely where you say that the decaying-c hypothesis is untestable.
Imagine a cloud of gas, or some other object that reflects light (perhaps the shell of gas from an ancient nova). Somewhere close by, a star goes nova, or otherwise changes its luminosity. If the star and the gas cloud are both 100 light years from Earth, and the gas cloud is 1 light year from the star, we would expect to see the gas cloud's brightness increase one year after we see the nova. If it took less than one year for the nova to illuminate the gas cloud, that would mean that that either astronomers are wrong about the relative positions of the objects involved, or that the speed of light has changed since it started out on its journey.
I wouldn't be surprised if this experiment had already been done, since I can imagine (real) astronomers being very interested in this question. A search of the relevant literature is, however, beyond the scope of this article, and is left as an exercise for the indentured servant^W^Wgrad student :-)