ndivuyo:
Actually I am asking in large part to get an idea of what rpm/voltage motor I should be looking at
don't the videos and other tutorials/writeups about these projects (it's been done many times) give you an idea of the rpm you need?
Next you need to know the torque required to spin whatever object you want to that speed. That torque is related to the air resistance encountered plus other resistances - while you can at least in theory calculate this, it's going to be a bit of experimenting to get a powerful enough motor. Look at what others used, copy that.
DC is much easier to control than AC (though for this project you don't really need to control the speed, as long as it's fast enough and you know how fast it spins). 12-24V DC is much safer than 240V AC. So unless you have a very good reason to not use a 12/24V DC motor, that's what you should aim for.
Anyway, for any useful motor advice: get numbers. What rpm do you want? What torque do you need?