I want to make sure I purchase the correct editing system for my Mac. I'm switching from Final Cut Pro to MAc - I have a New 27in Mac Computer. Do I want Adobe Premiere Pro CS6? How can I tell if it's for PC or MAc?
At the time of purchasing the software you can choose the operating system for which you want to buy it for.
If you want to buy it for MAC then Adobe will give you a installer and Serial Number for MAC.
Now you can also purchase Adobe software on monthly / yearly subscription, After purchasing subscription you can use the software On Windows and MAC both as per your requirement.
How are you purchasing the software: perpetual license? standalone or Suite? boxed or download? Adobe Cloud subscription?
Premiere Pro is often used in conjunction with After Effects and Audition.
If they will be part of your workflow too, you may be better off getting either Production Premium CS6 or joining the Creative Cloud (for a monthly fee).
Selecting Mac or PC (Windows) version when buying online is easily done at the point of sale by selecting the relevant option from the dropdown menu.