Oh, uh...nevermind. What was going to cost me over $600 in upgrades to accomplish (purchase of a new HDMI Elite 360 and a new home theater system that accepts/outputs HDMI) turned out to cost me $4 for a digital coax cable.
Apparently my Philips TV has an
SPDIF output, which I'd never heard of before, but outputs the TV's audio to my home theater system receiver (which accepts digital coax).
I had already purchased a 360 Elite, which I'm really enjoying, so that's fine, but it turns out that I didn't even
have to get that. Mental note: investigate all unknown inputs/outputs on new televisions in the future. We've only had the TV for going on
two years now, and I'm just now discovering this. :p