International Coach Federation
The credentialing and standard-setting organization for coaching.

Coachville
The largest coaching network / company / training organization in the world. Many free resources and information on their web site.

Christian Coaching Center
A huge, free, community of Christian coaches.

Peer Resources
A clearinghouse of information on coaching, coaching associations, books, newsletters, etc.

Gary Collins
Publishes a short, weekly newsletter on Christian Coaching. See his book here.