I believe Forgeworld is a part of the Games Workshop group, if not then it's certainly closely related to them. I was checking out their website today and they have some truly awesome models for sale (at a price !)
They seem to focus mainly on 40k but I found some great Fantasy Battle stuff as well like Rhinox Ogre Cavalry and an excellent giant (that's over 8 inches tall !)
For anyone thinking about creating a new Chaos Daemons army... there are 3 of the major Chaos Daemons (Nurgle Great Unlcean One, Slaanesh Keeper of Secrets and a Khorne Bloodthirster) under the "Warhammer Monsters" section - the level of detail is impressive, as is the size of the models.
Here's a link to their Warhammer monsters section:-
forgeworld.co.uk/acatalog/QUATERMASTERS_STORE_WARHAMMER_MONSTERS_1.html
They also make some very good looking terrain and buildings but you might want to forget where you left your credit card before you look at it:-
Forgeworld terrain:-
forgeworld.co.uk/acatalog/QUATERMASTERS_STORE_WARHAMMER_TERRAIN_8.html