Digital BW, The Print

I have recently purchased an 1160. Fitted it with MIS VM system. Most 
images are desaturated colour, from my Nikon D100. All images adjusted 
in either PS6 OR 7.
I have no past darkroom experience, so evaluating my results, are to 
what I like. I really, want to try and learn, to print Exhibition 
images and need to understand the print and evaluation process.
I use Paul Roark's curves, with varying results, mainly getting the 
correct light/dark.
Paul kindly sent me a step wedge. He also sent me "Tyler's Monitor 
Calibration Post".
Questions:
[a] How is the step wedge used, in the print evaluation?
[b] using Tylers Monitor Callibration, I got as far, as trying to 
adjust the dot gain curve.
When you bring the curve to screen, no adjustment is visible, to the 
image. Tried both PS6 and 7, same result. The reason?
All advice is appreciated. regards,Peter.