Google – by far the biggest broker of advertising on the net – is expanding its Adsense program into print, heralding the merger of online / offline advertising.

Adsense allows advertisers place small ads which crop up on the side of Google searches. Website owners can also place Google’s code on their sites and receive Adsense ads which fit the context of their content. The more popular key-words cost more per click. It’s also possible to advertise on specific sites that are members of the Google Adsense program. For advertisers large and small it’s very easy just to write a few lines of copy and become an international advertiser.

Next month Google will start a trial with 100 newspapers. The New York Times quotes Google on the commercial logic:

Tom Phillips, who runs Google’s print operations, said the company was attracted by the $48 billion spent every year in the United States on newspaper advertising. Google, nonetheless, is trying to position itself as a friend of the newspapers.

“Print adds value the Internet doesn’t have,” he said. Mr. Phillips, the former publisher of Spy Magazine, was hired by Google earlier this year. “It is a different browse-able reading medium.”

Exbiblio’s vision foresees a time when it will be possible to integrate an online / offline service like this even further, so that readers equipped with a portable scanner will be able carry out the equivalent of a “click through” from print to online. This would make the paper experience even more like advertising on the net.