If you have created the meeting workspace as the top level site collection, under site settings, go to site administration and select delete this site.
If you create the meeting workspace as a sub site of a team site, go to documents and list, click on meeting workspaces on the left and click the cross besides the workspace you want to delete.
If you create the meeting workspace as a sub site of another meeting workspace, go to site settings, and click on manage sites and workspaces, then click on the cross besides the workspace you want to delete.
Sorry, a bit long winded, cos I don’t know where you created ur meeting workspace in…