How to place an object in a photograph

[Daniel90]

I wanted to place an object modeled in Blender in a photograph that I've taken.
For this purpose I use compositing and blend my object with the AlphaOver node on top of my photograph. But now to the real problem:

I don't know where to place the camera (respectively the object), so that the perspective is right (the camera has to be on the same height and angle as the real camera). I couldn't find any tutorials or other sources that explain the technique.

I appreciate any help, thanks in advance!

[SirDude]

Look for tutorials on composting and color correction...

Here are a couple of things to get you started:

http://www.weirdhat.com/blender/compositing2/
http://www.colinlevy.com/tutorials.php