Well ... I guess the main problem about adwords is that you need to know what you're doing.

1) Make separate campaigns , one for search one for content network. They require different ads with different mindset to have a higher click through that would mean you would pay less per click

2) http://adlab.msn.com/Online-Commerci...n/Default.aspx ... find out for whickh searches the comercial intent is strong .. that means which keywords are buyers searching for ... this is the ones where you can put more money per click

3) have your own product ... it pays a hell lot more than being an affiliate. Have a low price product, build a list of buyers and high price product to sell to your existing customers that already know your product and trust you..