Where you live is totally irrelevant. What is important is your nationality. The only way to be absolutely certain is to ask the US Embassy
you need a passport.
Yes without a doubt you do
not again you need a visa to enter to canada
Usually a separate visa is required to enter England than to enter Ireland, so depending on your own circumstances, if you need a visa to enter Ireland then you will also need another one to enter England. There are proposals from the Irish government to let people who have visas for Britain to enter Ireland without having to get another one for Ireland. As of the time of answering this question (June 2011) this has not been put into place. Even when it does, they doesn't mean that a visa to Ireland will be acceptable to England.
yes just like everywhere else
Yes, everyone needs a passport to enter the United Kingdom.
yes It depends on your citizenship.
A valid US passport and a plane ticket
Yes. They need a warrant unless you give them permission to enter. It does not matter if you know the person or not, they either need a warrant or your permission to enter your house to search for anything including a person.
Yes, you do. Africa consists of 54 countries and you require a passport to enter any of them
Yes, a person needs to enter the coupon code included on the back of the mailed catalog. It is the number directly above the customer name and address. There is a place online to enter these codes when ordering.
A GNIB card only entitles you to entry into the Republic of Ireland. If you need a GNIB card to enter Ireland then you are likely to need a separate visa to get into England. The rules are different for different nationalities, so it will depend on where you are from and what arrangements there are between your country and England.