Here are a few other websites you might be interested in exploring:
First stop: Wikipedia! Find national and international associations, famous Spiritualists, places to study, and more!
http://en.wikipedia.org/wiki/List_of_Spiritualist_organizations
Summer programs at Camp Etna Spiritualist Camp in Maine
http://www.campetna.com/
Lilydale Assembly in New York
http://www.lilydaleassembly.com/