Ok... I try to read some tutorial of this argument.
One question if you know "at fly"...

1) I set the GraphicsUnit of Font and PageUnit to "Document".
2) I create a title string and measure it with "MeasureString" method.

Now, if i do this operation the text will be in center, right?
Operation:

StartPosX = WidthSizeOfDocument - WidthOfString / 2

The question is (also releated with your answers), how can i get at run time the size od my Page?