I was also looking for those figs from Eureka USA at Historicon when I found out they existed but he didn't have them.
After looking on the website I couldn't find them either. I'd probably buy a bunch. I have a ton of their Bosch-Chaos figures and love them, they are the marauders in my Slaanesh army.
On the subject of the Melniboneans above they will be used in a game October 9th at Phantom of the Attic starting at noon. The game is open to anyone that wants to come out.
Gaynor the Damned will be leading a Chaos Horde against Tanelorn.
The Gaynor figure is going to be the old Chaos champion with a two handed sword and a kind of spiky topped helmet. The sword looks like it has flames coming from it. I'll post a picture of him Thursday night.