Logic Pro 9 turned into a Power PC application?

I have used Logic Pro 9 for 1,5 years now. I tried to install a few plugins by IK Multimedia, and a couple of them went in just fine (Amplitube and T-Racks). When I installed Sample tank, it somehow changed Logic Pro, and now it won't start anymore. It says that Logic is a Power PC application and it's not supported. I bought Logic from app store as a download, and they don't have it there anymore. What should I do? Do I need to buy the new Logic Pro X or is there some other way?