The CPA was originally brought up by Baron Sengir on the Dojo message boards, using the original name 'The Sengir Army.' After the Founders emailed Baron with their support, we got together and started trying to figure out how to set it up. Ferret presented us with the name Casual Player's Alliance (Sengir Army is a tad militant, wouldn't you say?), and we stuck with it. After getting some hell from Newwave (*sic*), we joined up with magic-singles.com and Ed set up this site!
There you have it, the annotating version of the CPA history.
(I don't think we have an exact date for Baron's original post on the Sengir Army, but he suggested it a few days after Waylay was errataed, whenever that was. I think. Ed?)