Hubs don't even really become favourable to search engines until they are six months old; so none of your hubs are close to their prime yet. Keep working hard, this is no get money quick thing here; but it is something that will make you money in time if you continue to work at it
Also, I wonder if you're promoting your hubs anywhere? Putting them on Digg.com is the first place that I put anything of mine. Google finds links submitted to digg every hour; reddit is a good place to submit links, but it's a brutal crowd there, IMO. Facebook and joining facebook groups can work really well too.
But twenty cents is probably all that I'd made at that time too.
Also, I have to tell you that (not having seen your profile yet) that writing about products is what makes people the most money here, and if you really want to do article marketing for money, then you should concentrate on the products that you know and love, and write about those things.
I mostly DO NOT write about products, but I'm learning to enjoy doing some of that too.