Freestyle graphics
Albeit love can be ill-fated... by Panu Leppäniemi aka Xtrusi

1. Techniques

The image is a combination of multiple techniques, including photographs, 3D, but mostly hand-drawn images with a drawing tablet.
The photographs are free stock photos (from www.sxc.hu).

2. Stock photo source

http://www.sxc.hu/ (image license agreement: http://www.sxc.hu/info.phtml?f=help&s=8_2)
By registering to www.sxc.hu (anyone can register), you're permitted to use the stock photos on the site according to the possible restrictions that users have set to their images.

3. List of stock photos that I've used in the picture

Textures:
http://www.sxc.hu/photo/816844
http://www.sxc.hu/photo/812367
http://www.sxc.hu/photo/780899
http://www.sxc.hu/photo/786738
http://www.sxc.hu/photo/620009
http://www.sxc.hu/photo/638166
http://www.sxc.hu/photo/773734
http://www.sxc.hu/photo/806057
http://www.sxc.hu/photo/784531
http://www.sxc.hu/photo/754102
http://www.sxc.hu/photo/792981

Objects:
http://www.sxc.hu/photo/317018
http://www.sxc.hu/photo/372581
http://www.sxc.hu/photo/517158
http://www.sxc.hu/photo/673517
http://www.sxc.hu/photo/773708
http://www.sxc.hu/photo/763606