The newest Quicktime for Snow Leopard allows you to record in video your screen operation. It does not come with built in sound yet, but it's a start. I'll begin online tutorials now.
For stills, I use the built-in screen capture tools in Mac OSX Leopard.
Command+Shift+3 will do the full desktop (like Windows Print Screen).
Command+Shift+4 turns your cursor into crosshairs so that you can select your capture area.
Command+Shift+4…