Same with us. One deal or two a year for our yellow page ad. I suppose it depends on your geographical location too. People that call on our yellow page ad tend to be in a higher age bracket we have found so it also depends on your target audience. Paper and seeing in front of you still does hold weight to some as opposed to Googling something or someone.
We have had more traffic from our Yahoo Local listing and of course our referrals and people stumbling upon our search engine. We are still juggling around the idea of having an online listing, but I think we are going to pass ultimately. We will see. It is about that time of year when you start to get hounded by the ad people. Hold out for a good deal when space becomes necessary to fill ! ;-) Local newspapers in our area seem to be offering better deals for ad space, but we have received not a single call of them. Granted we are probably getting moderate face/brand time, but past that, nothing.
There are so many free places to advertise on the internet, but it does take time if you have it to spare (or a good job for an assistant).