Here's a good picture of an armouror's forge, and the pair of bellows with it's rocker shaft used.
Also, 2 pictures of my big medieval-style forge for (decently) small work:D.
I love how the pair of bellows works. If only I had me a pair:(...
By the way, I am planning to build a medieval-styled portable forge out of wood (see:http://www.iforgeiron.com/forum/f7/making-forge-out-wood-8038/). If I can finish it soon enough(), I will post pictures...