There's a good poetry session by Soul Food Productions, been going strong for about 3 years now. @ Bloomsbury Sq, UCL premises. every last sunday of the month. check out their web.
www.afropickproductions.com
Also check out, The Oh Bar in Camden, every first Sat. of the Month. can't remember the times. but if you contact them, you should get more info.
Apples and Snakes in Battersea. I've been twice, it was absolutely wicked. Contact the Battersea arts centre for more info.
New Nation usually has a good segment on the Spoken word on venues in and around London. Might be useful getting Monday's edition.
Hope this helps.
peace.
Kwela.