Pay per click to advertise?

[Jake]

While Adwords can deliver highly qualified prospects interested in your subject, it can be big money loser for all but those store sites with optimized sales pages and finely tuned ad campaigns.

Cost per clicks is more like $0.50 to $5.00 in most cases, depending of the competitiveness of the keyword selected, commonly sales pages make a sale to 1 in 25 to 100 visitors, meaning the cost of a sale could range between $12.50 to $500 you can see how optimizing the sales funnel and careful keyword selection can make a big difference.

By all means set your daily spend limit to a reasonable number, the wrong combinations of settings could almost bankrupt you. If planning any significant expenditures, be sure to study all you can, a separate paid book or course beyond Google's info may be a big saver, there's probably a video course on Lynda.com.
http://www.lynda.com/search?q=adwords&x=0&y=0

Another self serve ad system that's not bad to start with for more consumer oriented marketing is Facebook paid ads, the approach is quite different, while you can get people focused on a problem you hae the solution for through Google sponsored search, you are interrupting people's social meanderings on Facebook, typically the ads have to be more superficial, the photo must be a standout to break through banner blindness. The big Facebook advantage, terrific demographic targeting setting, you can specify you only want to be seen by Engaged women, living in your city between 18 and 30 it will give you an advance estimate of the potential number of members you can reach. This data can be useful for various market research, like considering a franchise store location.

Both of these ad systems have first time user only vouchers of $30 - $100, don't miss out on that.

The Keyword Phrase Selection process you apply to sponsored search ads can provide a list of phrases you should also incorporate in your content to raise your "free" organic search ranking and traffic. Some write a separate article focused on each major keyword, including it in the title.
(They also have an ad network where you pick sites)

Anyone can use the Adwords keyword tool for research and get 10 results, logged into an Adwords account you get 800 results and more columns like click cost.
https://adwords.google.com/select/KeywordToolExternal