A friend of mine recently recommended me to iwriter.com. He's quite content with the works he's gotten and speaks very highly of the site. I think you can find writers of all sort of areas there.
I have not hired anyone from there though so i can't really vouch first hand but i do plan to some time in the near future hopefully.
Your price of only $1 for 100 words is only going to get you crap articles. That is only one cent per word, and is an insult to any writer who takes pride in their work and writes quality articles. JMO
There are a billion and one experiments in getting the customer through the door and i have no doubt that karl rove made the next US president (god forbid) with a direct mail campaign that got out of hand. Lets hope they bounce.
That said, by all means riddle the ten billionth worthless page on the web with "SEO rich content" and count those clicks. Intellectual sweatshops are a tappable resource. Have at them.
But what happened to attracting and promoting? I refuse to believe that the important players here in this industry actually view (god forbid) their click and conversion count - by any means possible - above running a business that offers a service to their customer - an introduction that matters.
If any one does, only care about conversions and numbers and their bottom line? I'm in the wrong house.