Sonic - you're correct.
Todd - you're correct as well.
Exposure is key - this week we were in the New York Art Expo with an artist who's known mostly in pulp comics and on DC Comics titles. Now, since the show, his stuff is selling very well - original oils for $4K and up (though we also have less expensive prints). I think we've sold six this week alone.
We act as agents and publishers. But we would have never known about this guy unless he approached us.
So the rule is: execute and send it out. Sooner or later someone will notice your work and potentially purchase it.
And never fear agents, publishers or studios. They have more to lose by
not looking at your work than by you sending it to them.