In Tokyo I can't remember the last time I saw a print ad in a public space that had an actual URL. Increasingly what you see instead is a stylized image of a search box (pixelated white box with a magnifying glass button on the side and a mouse or hand icon touching it) with some phrase inside the box indicating this is what you should search for to find more information about the ad. Amazingly the search term is usually so brief and general that I wonder if Yahoo Japan is selling the right to appear as the top search result to the advertisers.
Wonder no more: Yahoo Japan sells exactly that. So does Yahoo US: it is called "paid inclusion", and is sort of a dirty secret.
In my experience though, while the search terms are brief, they are usually not general, because they use Japanese other than what would naturally type to describe the product. For example, a tagline on a JR ad on the train today worked for me: "We can recommend you good lodgings. Just search for JR good lodgings." However, just like "good lodgings" is a little bit forced in American English, いい宿 is a little forced in Japanese.
Another favorite is making up a word in katakana. If you make up a word, you're going to own the search engine results for it by default. (Hint: works great for ideavirii. Think O'Reilly regrets "Web 2.0" one bit?)
And you'd get no argument from me.
I don't think enough people have come to terms with the fact that for the average Internet user, Google is the Internet.