I found this video on Youtube, just browsing:
It is not an in depth study, but it is made for anyone who would like to get to know the Adwords advertising program. Its a great watch for when you need to relax.
Basically, Adwords lets you advertise through Google search network, as well as content network and partner sites.
In contrast to SEO, which influences organic results, Adwords is a tool that helps you manipulate and manage pain advertising. The viability of paid advertising has probably been discussed to death. In short, it is viable for SOME products, but you really need to do your homework before embarking on a serious Adwords campaign. Thankfully for us, Google is well aware of that, so it has been distributing coupons for Adwords for some time. With it you get about 100$ for a 20$ investment (coupons vary by the funds you get). If you have some spending money, you might wanna test run Adwords at some point.