I just purchased a mac and I have Premiere Elements 11 on mt pc, how do I get the program onto the mac?
You cannot install a windows version of Elements 11 on a Mac.
You need a Mac version, unless you have installed windows on your mac.
I have the disks for mac for elements 9 but I believe I purchased 11 online. Do I have to purchase 12 for a mac and will all my photos and video be put into the 12 version?
One of the perks of buying the packaged product is that is comes with installation discs for Windows and Mac. And, you can use your one purchased serial number for either. When you purchase online, typically your installation files are for Windows OR Mac, not both.
You can verify all this with Adobe direct (this is not Adobe), but you cannot use Premiere Elements 12 in any way without a purchased serial number for it. If online purchase, the download is going to be specific to your Windows or Mac.
My suggestion would be to go with the free 30 day tryout of the program from Adobe to make sure the program is compatible with your computer environment and that it meets all your video editing needs. If it does, go with purchase of packaged product from an authorized reseller. (Adobe direct appears to be offering ONLY the download for purchase). With the packaged product you will end up with a installation disc Windows and an installation disc Mac.
Please check out the above and, if any questions, please do not hesitate to ask for clarification on anything written.
Add On...The above is my latest understanding of the situation that you present.