I would first go to your username>library>preferences and delete. com.adobe.Elements Organizer.10.0.plist and com.adobe.ElementsOrganizer10.plist.
That will let you start up and open the catalog manager, because it will make organizer forget which catalog you were using before. Then follow the rest of MichelB's instructions.
To see that library, click the go menu in the finder and hold down the option key and it will appear below the little house for your user account.