Depending on how you consider "ethically-focused", it could be easy or difficult. If you're wanting a job at an organization for world-based improvement, you'll be more likely to find a job by visiting their website directly. If you just want a company that tries to promote well being for all people and the environment, you could search on any job-related website.
Organizations would most likely pay less than a corporation (although both are corporations, one's just nonprofit). The more a company relies on donations to operate, the less the pay would likely be. So it all depends on what you want.
Of course there are actual corporations that are ethical -- promoting well being for all people, less use of the environment, recycling and other green activities, as well as giving back to the community in money and programs; all while being truthful and offering things without catches (i.e. free stuff without advertising, or without a paid membership to receive the "free" stuff). But they are most likely harder to find, and if you do, probably not hiring.
I know, I'm the president of such a company.