Yomiko appears in exactly one story, at the end of the series, sort of looping it back to its genesis in Read or Die. Nenenenenenenenene *smacks self* never appears at all. The focus is entirely on the Paper Sisters, and their own extended supporting cast (Hisa, a young fellow named Chihon, a man named Mr Lau, Lily the Reader Extraordinaire, etc).
ROD the TV is rather an alternate universe to the manga (which debuted at about the same time - the manga had a couple months head start) - the overarching story isn't there, and Read or Dream is a lot lighter, being more character driven than actiony. Not that there's no action, but it's not nearly the focus. There is a bit of an overarching story, but it's a completely different one, involving a smaller group of characters, and no big global conspiracy. One particularly interesting change - Anita's history in the manga is all there in the anime, but it's not all Anita's history. (Ooo, cryptic! But it's majorly spoily to say anything else.)