The ietf-charsets mailing list exists for the purpose of discussing charsets and charset registration issues. Background information on the charset registration process can be found in RFC 2978.
To post something to the ietf-charsets list, send email to ietf-charsets@iana.org. An archive of the list is maintained here.
To request a subscription to the list, send a request to ietf-charsets-request@iana.org. (note the -REQUEST part.) Using the latter address will prevent embarassment you would otherwise suffer if you sent your message to the entire list.)