I think the hardest part is actually sitting down and doing the work. Writer's block can be something that you have to deal with. The key is to just write and write. I try not to focus too much on how great something sounds. I am just trying to get stuff out there and hope someone clicks on ads.
I have one article on ezine. It doesn't pay anything and is only useful for links. I don't yet know if it is worth the trouble.