As you may know, the Pipe Organ Database currently only accepts information about instruments existing or built in the continent of North America. If you are looking for information about pipe organs in other continents, the links below are a good place to start.
This website, run by the British Institute of Organ Studies, is working to document all of the pipe organs in Great Britain. It has many good tools to allow you to research the items contained within.
This website is working to document many of the pipe organs in Europe. Many of their entries are not in English, but they are working to translate them all for the future.
This website documents information about Australian organ history and has a a small database of instrument specifications from the area.