Iron Kingdoms RPG is now out of print. However, Privateer Press have announced that their IK RPG books are now available as pdf downloads:
http://privateerpress.com/company/iron-kingdom-rpg-source-books-now-available-in-pdf
The following books are available from Drivethru; the links below will take you directly to the product page to buy them:
- PIP004 – The Witchfire Trilogy Collected Edition
- PIP202 – Monsternomicon Vol.1: Denizens of the Iron Kingdoms
- PIP203 – Monsternomicon Vol.2: The Iron Kingdoms and Beyond
- PIP401 – Iron Kingdoms Volume 1: Character Guide
- PIP402 – Iron Kingdoms Volume 2: World Guide
- PIP404 – Five Fingers: Port of Deceit
- The Umbral Spiral
- Fool’s Errand
Note that Matt Wilson announced in an early 2010 interview that PP were working on a new version of the IK RPG using a proprietary rules engine that is based on the core WM/H mechanics:
http://forgegames.wordpress.com/2010/03/22/new-ik-rpg-in-20112012/