The UK Messaging and Mobility User Group (MMUG) has two events in August, the first in London covering Windows Mobile Business Apps in one half and an Introduction to Office Communication Server in the second. The event is on Thursday the 23rd August and you can sign up here:
http://www.mmmug.co.uk/forums/thread/1340.aspx
Finally, they have their first meeting in Liverpool which will cover a mixture of Exchange related topics including Exchange 2007, HA with Net Apps Filers and also a look at OCS 2007. Again for more info and to sign up see the link below: