There is a reason why people need pay per click management. It is simply too easy to set up a Google Adwords (or other PPC) campaign incorrectly or inefficiently.

I recently took over a campaign for a client who had put around 200 keywords into two different ad groups with a total of two ads between them. It is a lot faster to set up a campaign by entering all of your keywords into one ad group like this, but it can really hurt your campaign.

Everyone knows that word of mouth endorsements are generally the most effective and most desired form of advertising. They are free, generally self propagating and are also the most effective long term form of advertising in any medium. This is due to the generally accepted idea that people listen to, and trust, their friends.
Here are two excellent books that you can get on the subject:
Word of Mouth Advertising Online & Off by Lynn Thorne