I'm trying to find the e-mail address of Sunday Times(London Times)
writer and food critic AA Gill.

Dear andrewf444,

AA Gill, best known for his work for The Sunday Times, is also
Editorial Director of Travel Intelligence, an online hotel guide. As
such, he has an e-mail address:

aag@travelintelligence.net

There is absolutely no doubt it is the right AA Gill, since the list
of Travel Intelligence's writers says:

"AA Gill
AA Gill is a features writer and critic for The Sunday Times and GQ
magazine and writes regular travel features for The Sunday Times
magazine."

Sources:

Travel Intelligence: About Us
http://www.travelintelligence.net/wsd/html/aboutus.htm

Travel Intelligence: Writers
http://www.travelintelligence.net/wsd/html/writers.htm

Search terms used:
"a a gill" contact
://www.google.de/search?hl=de&ie=UTF-8&oe=UTF-8&newwindow=1&q=%22a+a+gill%22+contact&meta=

Hope this is what you were looking for!
Best regards,
Scriptor