I'm trying to uninstall MAMP and MAMP pro from my mountain lion macbook and don't know how i should do that. I tried dragging the icon from my launchpad to the Trash, but it doesn't work.
What should i do?
MAMP has a specific uninstaller in the disk image you installed with. Mount that disk image and you should see the uninstaller. Go here for more information.
For the rest of your apps that don't have specific uninstallers, use AppZapper, which is a nice utility. There are a few alternatives (CleanMyMac has a built in function for this) http://www.appzapper.com/
Go to the Applications (it should be in the sidebar of the Finder) and drag the app into the trash from there.