How do I make a normal/displacement map when all I have is a photo? In order to make a rendering look more realistic some additional maps are useful.

The documentation lists: diffuse,specular displacement-maps .

I watched a video tutorial The Secrets of Realistic Texturing which uses a commercial tool. 

Are there any alternatives to calculate normal and displacement maps from an image texture, or can this also be achieved by some build-in transformations?

NOTE: As requested, this is related to image-textures that have been downloaded from a site like cgtextures which are image-only and lack of normal- and displacement-maps.
I've compiled a list of options when it comes to normal and bump map creation. All that remains is to try few of these out and see which results you like best.

To me, the most advanced of the free solutions is MaPZone 2.6, but I haven't tried any of these so I am not sure.

Or you can try the web based Smart Normal, for very basic normal maps generation.

Another tool is  Knald which offers high quality, accurate height maps generated from a Normal/Derivative or photo-sourced texture.

I didn't include urls, since they can be easily googled.