The answer to question one...Select a stain you think would compliment the pipe and apply it. I have an unfinished Nording that I have allowed to stain by smoking. It went from white as a baby's butt to a reddish color. The more I smoke it the more it colors. The oils go tight into the pipe.

The answer to the second...I don't have a clue as how to apply a stain or finish a pipe. There are pipe making forums on the net that might offer some help.