There's only one club (that's a member of the national association) in what I'd call 'proper' East Anglia. It's in Norfolk. If you widen your range to 'extended' East Anglia, there are clubs in south Essex, Bedford (for the ladies) and Lincolnshire:
http://www.tugofwar.co.uk/3234.html
There's also a team based at Great Totham, between Witham and Maldon:
http://www.tugofwarfederation.com/members/
There are also individual events, including those organised by Young Farmer's Clubs (often linked to county or regional shows) and those incorporated into local village fetes, etc.
Are you looking for anything in particular (or perhaps just the opportunity to admire some big, hunky men)?
;-)