Article marketing is a great way to promote CPA offers because people will get something for little or no cash initially. People may think twice before spending $20-$40 for a Clickbank product. Although Clickbank products are still a good way to earn if you are consistent in your efforts.
Wow. This post was really helpful. Might even earn my vote for the post of the year! As for the question, it doesn't really matter whether you promote a CPA offer, a Clickbank product or your website - at the end of the day what you're promoting is a certain landing page and the methods you can use to bring traffic to the landing page remain pretty much the same regardless of what the landing page is selling. I'm not going to give you a list of tactics you can use to get traffic though, simply because this topic has been covered here thousands, if not tens of thousands of times.
The best, and the hardest, way to promote your products is PPC. So make sure you learn every single thing about it before using this method; otherwise not only you will lose some money, but you will get the (wrong) idea that it doesn't work. I heard about people making a living off of PPC, so it does work; but make sure you learn how to handle it first.