Here are several professional organizations and conferences that I feel are great!
National Science Teachers' Associationhttp://www.nsta.org
National Council for Teachers of Mathematicshttp://www.nctm.org
Texas Computer Education Associationhttp://www-tcea.cc.utexas.edu/html/tcea/tceamain.html
American Association of United Women ????http://www.aauw.org
Center for Research on Parallel Computation, a National Science Foundation Science and Technology Center - GirlTECHhttp://www.crpc.rice.edu/CRPC/Women/GirlTECH