Now, there used to be a link to chinahistoryforum which covered Cao Cao's lesser-known sons. But when I checked today, the page is gone -- and archive.org didn't record it because of the site's robots.txt.
So I did a bit of googling, and lo-and-behold, I found a page with a wall of text (think one paragraph 200 lines long or so) including short bios of Cao Cao and Cao Pi's lesser-known sons, relevant ladies, Cao Song, Cao Teng, and Cao De. There's also a brief history of Wei and of fictional officers from the novel.
However, there's one problem: the chinese (.cn) page it's on is infested with ads (at least two of which slipped by adblockplus, and no less than three popup ads were only blocked by a firefox setting); while MBAM didn't find any viruses, I just don't feel safe sharing it publicly, as other people may get infected. But the alternative is giving the bios yet not giving them any credit (even though the "one giant paragraph" means it was very likely copied wholesale form another page).
Anyway, I have a copy of the bios; if the mods say it's okay, I'll post them here.
Unless I specifically say otherwise, assume I am talking about historical Three Kingdoms, and not the novel.