Is it permissible to eat the meat slaughtered by people in Japan who are not People of the Book, but who slaughter for consumption and not for idols? And is it permissible to eat meat imported from Australia or America (People of the Book), despite the availability of halal meat which requires effort to obtain?

It is not permissible to eat the slaughtered animal of a non-Muslim or a Person of the Book because it is considered carrion (maytah) due to not having been slaughtered in accordance with Islamic law (dhakah shar'iyyah), and Allah has forbidden carrion. One must be careful not to interpret the Qur'an based on personal opinion, as understanding the Quranic text requires knowledge of the Arabic language and Hadith sciences. It is not permissible for a non-specialist to derive rulings directly unless they are very clear. Whoever wishes to eat meat should seek out halal meat.