This one requires a little upfront expense (sometimes) but the conversion rate is so high its ridiculous.
The first thing to do is to open up your YellowPages (dead tree version) and go to the Restaurant section.
Now what we are looking for here are businesses that have paid for an ad in the YellowPages but do not have a website (or a facebook page/google local etc ).
Next thing I want you to do is pick up the phone and call them. Once you get them on the phone resist all urges to pitch them anything. Instead, make yourself a dinner reservation for around 8pm. This is usually a good time as any earlier they are busy and any later they are packing up.
Gather your sales materials and take them with you to dinner. Sit down and order yourself a meal and enjoy it. At the end when the waiter comes to hand you the cheque ask if the owner is available (they always are).
The owner will come over. Introduce yourself and compliment the food and service, say how you loved the atmosphere. Then explain to them its a shame they are missing out on so many potential customers (begin pitch) make sure to emphases the benefits of what your proposing over the YellowPages ("Did you know that less than 10% of people use the YellowPages as their first point of reference when searching for businesses?" "If you don't mind me asking how much did your YellowPages ad cost? Wow that sure seems expensive when you know that your missing out on 90% of people that are looking for you" etc) . If they do not have time to chat, make an appointment and leave them some facts to mull over.
If you have some solid material to present them and your a reasonabley convincing salesperson you will close a sale easily on the night (and most of the time your dinner will be on the house too)
HOT TIP: Take an iPad to show them what their competitors are doing.