Thri-kreen are also in the XPH, Mist Dragon is in Dragons of Faerûn.
Dracolisk was done as a half-black dragon basilisk in the Draconomicon web-enhancement. (And yes, it did say Dracolisk).
Amon, Duke of Hell is in the Book of Vile Darkness Web Enhancement (under the Servants of Geryon)
Spider, Giant Marine was technically adressed in Stormwrack, in the Aquatic animals section.
IIRC, Dragon Horse was done in Dragon Magic.
Also, I keep thinking I have seen the Gloomwing somewhere .. Monsters of Faerûn??