It might be useful for people to contribute to a database of TG-friendly professional or work-related associations. Maybe also TG-friendly recreational clubs.
I'll start!
Gay and Lesbian Medical Association
http://www.glma.org/
Association of Gay and Lesbian Psychiatrists
http://www.aglp.org
Transgendered American Veterans Association
http://www.tavausa.org/
Blessings, Tara