Creating bump maps from colour maps
I'm about to start work on my first attempt at texturing anything (I've been practicing modelling for ages - time I tried something else!). I'm going to be texturing a building that I have made, and I want to give the bricks that '3D feeling', without having to model them, so I am going to be using a bump map (possibly displacement, depending on what you guys think is the best solution) Now, I already have the colour map that I am going to use, but it doesn't have an associated bump map. What is the best/easiest way to create the bump map? I'd appreciate any links to tutorials, or just answers posted here.
'England Expects That Every Man Will Do His Duty' - Vice-Admiral Horatio Lord Nelson - Battle of Trafalgar - 21st October 1805