Infobarrel is a writing site too just like ehow ,bukisa and triond. but their adsense features are very different than the others. You only need an adsense account to signup on them and let them to the job of posting your ads on your articles.
Another good this about Infobarrel they check first the little before they let you write your article and it takes 1-2 days before they confirm or dinied your article. The factor of being denied your article is
1. you copied your articles to others
2. even your the real author of that article but you still copied it from the original site.
3. similar to others (even tho its on your own words)
After your article is being reviewed and confirm you can now view and share it to others to make you a higher traffic (remember your adsense account ID you gave them to post an ads on your articles so you need more traffic on that.
But of course its your adsense ID so remember that your still on the TOS of google, don't try to trick or cheat, their watching you if you don't know.
So remember your TOS or review it again before doing such as trick or cheat.