Here is a map of gyms in the region where badminton clubs are active. If you are interested in becoming a contributing editor, contact Peter. The idea is that we make this another good resource. The current version may look a little DC/Baltimore centric, but we're going to change that: http://maps.google.com/maps/ms?ie=UTF8&hl=en&source=embed&msa=0&msid=200466645644367708604.0004803d795cee29a2452&ll=39.110883,-76.920776&spn=1.40013,2.158813&z=9