If ads don't show up in Google after activating your AdWords campaign, chances are there's one problem with the account, but several possible reasons why. Carrie Hinkle provides a checklist of 10 reasons why your ads aren't showing up in Google.
For example, "active" vs. "paused," a fundamental element for any campaign may seem intuitive, but just make sure your account, campaign, and ad group settings are set to "active," Hinkle writes. She suggests beginning at the top and working your way down the list. By the end you should solve the problem.