AdWords advertisers can now select which sites can display their ads 
Google said late Tuesday that it would offer its advertisers the ability to select which third-party sites would display their ads.Google will begin beta testing the new program in March.It also said it would begin charging for the ads on a cost-per-click basis instead of the cost-per-thousand-impressions, or CPM, basis it presently uses.Google said it was accepting applicants for the beta test, …