The idea is test out different niches. I make a high 4 to 5 figure monthly just from Clickbank. My strategy is simple. 1. Create a blog on a niche 2. Write 10 to 20 articles to promote the niche blog. Submit them to EzineArticles and mass post to hundreds of article directories. 3. Observe if it converts into sales. If it does, ramp up the articles. If not, drop the niche. PPC can be expensive if you do not know what you are doing. It is best that you do the first level of litmus testing using articles. Once you have a rough gauge of its profitability, then use PPC to promote. Don't fight for the top spot in PPC search. Try Google placement instead.