Warlord Games has specials running for many of their rulebooks and supplements over in their webshop.
From the announcement:
We appreciate lately that some of you might not believe this but we do have other cracking rule systems besides Bolt Action!!
We have decided for the rest of January 2013, that is until the 1st February 2013, to offer a hefty discount on Hail Caesar, Black Powder and Pike & Shotte making these great rules sets even more accessible.