I'm running CS5 (Old yes, but still suits what I do).
My 'transform' window, for some reason isn't wide enough The blue 'shear' button ant the 'link' button (that constrains proportions) are missing and I can't figure out how to make it wide enough...
Double click on the word Transform in the transform pallette. Do it again for a different size - it has four sizes if you include just the word. Five if you include the double arrow click to minimize.
There's also miniscule arrows on the left that do the same thing...