This is a script that creates camera according to perspective lines on your image. It is sort of a beta version and has no error handling yet, so be warned:).
1 - get an image for which you want a camera being created.
2 - run the script (it is ordinary maxscript).
3 - press first button in UI and select the image
4 - an image plane and helper curve will be created
5 - modify helper curve (subcurves) so that they follow perspective lines, the vanishing points with three pairs of subcurves
6 - press the second button in UI, the camera with correct FOV will be created and another one, aligned to the image. That's all.
Testing needed, my tests show good results.
Acknowledgments go to sanctus (http://somesanctus.blogspot.com/), who made a similar script for maya, thank him a lot for the main idea.
how to use mini tutorial - http://andklv.narod.ru/tut_mini/minitut_10/111_cameraMatch_tutorial.html