I'd recommend checking into CreateSpace - I've done an enormous amount of research into print-on-demand services this year, and CreateSpace has the best total package (cost / ease-of-use / broad distribution) at the moment.

Lightning Source is also worth looking into for direct distribution, but if you intend to sell on Amazon, CreateSpace is the service to beat.

Check out https://www.createspace.com/pub/l/general_amazon.do?rewrite=...

(I work at Amazon, but not part of the MoD teams)

I hope you print it on recycled paper. Dead tree reincarnated is better.