Question: Can I eat zabiha that is slaughtered by machines?

Answer: No

Question: Can I eat the zabiha of the Ahl al-Kitab (People of the Book)?

Answer: Most Shia scholars say that it is not permissible. However, a small minority of them, along with many Sunni scholars, say that it is permissible. Those Shia scholars that permit it have much stricter conditions than the Sunni scholars who permit it.

Question: Is it permissible to eat the zabiha of Sunnis?

Answer: Yes, as long as the zabiha is hand slaughtered. 

Question: Is any animal that has been properly slaughtered halal according to Islam?

Answer: No, only animals that are first permissible to eat can be slaughtered. Pigs for example, even if slaughtered through zabiha, are not permissible to eat.

Question: What can I do if there are no halal restaurants or halal meat markets around me?

Answer: For restaurants, you always have fish or vegetarian options. For meat markets, a good tip is to go to one of the further markets once in a while and buy a large amount of halal meat, then bring it back home and store it in a freezer. If this is not possible, there are plenty of vegetarian meat substitutes that are made with soy.