Given that the host this box is on actually costs me $110.95AUD every thirty (30) days to run, $9.90, as nice as that is -- still will cost me over $100 AUD to distribute the code at all.
No, that's the "I paid $20,000 to buy this webserver, and the bandwidth is $200 per gigabyte, and you're the only person asking for the source so you have to pay all of it" argument. The GPL isn't meant to cover the cost of a CD burner, merely the cost of the media and postage. It doesn't cover the cost of your connection, but it could cover the specific cost of the bandwidth (if you're charged per byte). If it genuinely costs you AUD5 to send 50MB or so, then fine. But you made it sound like the money was supposed to cover the time and effort you put into it, and that's not fine. If you're distributing GPLed binaries to people, you either give them the source at the same time or you provide the source at cost.
And, for what it's worth, the correct response to a polite note from a copyright holder requesting that you conform to your license obligations is generally to apologise for breaching their license rather than , say, posting a petulant whine. Especially if you're counting a request to conform to the license as a "request to remove the code".