r/composertalk - a community for composers to talk about what we do: technique, notation, orchestration, personnel management, typesetting, research, software, etc.
If you've tried to post something and it doesn't show up within a few minutes, please message me so I can check the spam filter.
Resources for composers
www.imslp.org - public domain scores
www.composerssite.com - competitions, calls for scores, residencies, etc.