These are some of the new regiments featured in Games Workshop's Warhammer supplement, Dogs of War, a book featuring many mercenary regiments that are available to most of the available armies.

Alcatani Fellowship
Braganza's Besiegers
Beorg Bearstruck and the Bearmen of Urslo
Bronzino's Galloper Guns
Marksmen of Miragliano
Asarnil Dragonrider and Greenfang
Mercenary General and Lucrezia Belladonna
Leopold's Leopards
Golgfag, Mercenary Ogre Captain
Long Drong Slayer's Pirates
Birdmen of Catrazza

New Regiments of Renown for your armies to hire!

Pearl Dragons
The Crimson Eagles
Ragnar's Wolves

Non-Human Mercenary Generals
(Note: These are not the WD 234 rules)