There are many asset companies which now hold offices located worldwide. It may, therefore, seem that you should be able to contact the one closest to you to attend to any assets held internationally by the same company. For example, you may have found some shares registered through Computershare in the UK but be dealing with Computershare in Australia also.
Unfortunately, although sharing the same name, you will find that most of these companies do not deal with their international counterparts and are in fact completely unaware of the processes involved to try and repatriate assets.
Sometimes, trying to deal with international assets through your local branch can, in fact, cause delays and further confusion. It is therefore always recommended that you deal directly with the branch where the asset is registered.