Does the time zone in a mail header help me to identify the country of origin? I sent this from Ct USA eastern time last night. When he replied it says GMT. Does this mean he is in England or another country).
All we can deduce from this is that the sender is using a computer (or an iPad) on which the time zone is set to GMT+1. If accurate this means western Europe or parts of Africa. But as everybody can set their computer to whatever time zone they like it could be from anywhere.

For more information about time zones see the Time Zone Map or the Time Zone entry on Wikipedia.