A recent Google search turned up the Accompanists' Guild of South Australia, created in 1983 and serving the area around Adelaide. A description of the guild's purpose is worth a look:
The Accompanists’ Guild of South Australia Inc. was founded in 1983 as a non-profit organisation. Its objectives are to promote the status of the accompanist and to encourage and assist in establishing a unity of purpose and the maintenance of high ideals amongst accompanists in South Australia. It also provides a point of contact for accompanists and other musical groups on matters of mutual interest.
The Guild organises musical programs throughout the year in which various aspects of the art of accompanying are discussed and demonstrated, using South Australian performers and guest artists from interstate or overseas.
In addition, the Guild organizes noon hour concerts, a Young Accompanists' Showcase, raises money for the $2,500 Geoffrey Parsons Award, and has also recently acquired government funding for their endeavours. Membership is very reasonable ($55 regular, $10 student, $25 associate, $500 life).
Since there are already numerous registered music teachers' associations around the world providing referrals, professional development, and scholarships for talented students, why not create such an organization for those of us in the collaborative arts? We're not such an unruly bunch--are we that difficult to organize into groups?
Kudos to the AGSA and what they have accomplished--let's hope that more organizations of this sort start popping up.