Definitely use a pipe cutter for the steer tube. I use one of these:



It will give you a clean and *even* cut.

For removing the crown race, there are special tools for it, but I use a flat head screwdriver and I tap around it gently and patiently. Just take your time with it and go around it evenly. It will eventually come loose. For installing the star nut, I use one of these:



There are better star nut tools out there, but that one works just fine and it's not too expensive.