The Barony of Nordwache maintains an unofficial mailing list on a Yahoo group: baronyofnordwache.Other mailing lists that may be useful -
Caid: http://www.sca-caid.org/commons/index.htmlThere may be others, which will be added here from time to time.
SCA: http://lists.sca.org/listinfo
Historical Costume: http://mail.indra.com/mailman/listinfo/h-costume