It's amazing at what you can find on the Internet, when you put some real effort into your searches. Wouldn't you know it, I came across yet another fertile resource for Commodore 128-specific software. This time, it's an archived version of the dial up service, known as GEnie.
It was a dial up service that was in service from 1985 through to 1999, ultimately being replaced by the Internet and on-line services, like AOL. More about GEnie can be found here, on Wikipedia. And the link to the GEnie archive, itself, can be found here: http://www.cbmfiles.com/genie/index.php
In this archive, sponsored by Click Here Software Co., there's a plethora of software for the Commodore 128 and 64. You'll even find some software written for the C128's CP/M mode. One of the little gems I found, so far, was the game Astra: Invasion 3, which runs in 80 column mode on the C128. I recently did a review of the game, here.
Who knew there was so much good software out there, for the C128?