Newbie Alignment and subdivision question

[Fonte Boa]

how can I align one shape 'face' to those of another shape without deforming both shapes? Up to now I simply get the X, Y or Z coordinate of the face I wish to align to then I do an absolute move (checking 'moving object') of the matching face in the shape I wish to move. The result is good but I hope there's a some more easy and speedy way.

If i understand right:

( a ) Select the face to be aligned
( b ) Left click in Face|Put On command
( c ) Click on the target face and right click to Execute