Focal Distance:

Auto focus expression (advanced):

http://motionscript.com/design-guide/auto-focus.html

Lights:

 

Screen shots from the video above:

Materials:

 http://tv.adobe.com/watch/learn-after-effects-cc/introduction-to-3d-material-options-environment-layers/

Here are a couple of other advanced techniques to build a 3d scene:

Vanishing point:

( Thanks Hyo Bin for this tutorial)

 

Camera Mapping:

 http://www.videocopilot.net/tutorial/submerged/

 

3D displacement maps:

Same technique ( Depth map):

 

 

3D Text and vector shape extrude:

Advanced:

http://cgi.tutsplus.com/tutorials/real-camera-inner-workings-within-after-effects–ae-21497

http://www.videocopilot.net/tutorials/submerged/