Welcome to the world of expensive light! I too am fairly new but I know quite a bit, and I'm sure others will come in to correct me if I am wrong. You most likely will either have to get boot camp or a pc to run the software used to control lasers. You 'could' get a DMX laser but it wont give you nearly the amount of options as you get with an ilda compatible one.
The projector that you buy will have specifications for the scanner that comes with it (the mirrors that bounce around your lasers) since you are interested in beam shows and not graphics, something in the 15-30K PPS (points per second) range should be sufficient. Others on the forum will be able to give you recommendations on where to get these parts.
Realize that lasers will cost a lot and if you are looking for a place to save, I suggest starting out with only one color of lasers.
Im sure my bud DSLI Jon will come in with safety information; a huge part of the laser life
Freelance Laser Operator in L.A.
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