Here's Michael Martin of Business Information Arts, coordinator of the Toronto Tableau User Group. We have been meeting mostly monthly, sometimes bi-monthly since July of 2010. Our meetings are free and open to anyone interested in Tableau.
Each meeting typically includes a presentation of specific Tableau features and examples of how they could be applied in a "case study" format, an "open mic" discussion where attendees share tips and tricks, and time to informally network with other group members.
Please write to me at firstname.lastname@example.org if you have any questions about the User Group or would like to attend and / or make a presentation at an upcoming meeting!