Really could be a very long list, so here just a selection.
This list is by no means a complete overview, but rather a selection of galleries/outlets we frequent.
Some websites carry listings of opportunities, awards, grants and the like.
There are a variety of ongoing festivals that are always looking out for creatives to fill their programmes. These often have huge lead times so be sure to check them out early and thoroughly.
Apathy is not an excuse but rather a vote of support for the status quo.
... are the best thing since...