Ingenio has linked up with Web search engine Find.com to provide pay-per-call listings in its search results. Pay-per-call is getting more and more attention these days as a valuable source of performance-based marketing, online and off.

Click-to-call (the basis of a pay-per-call business model) was integrated into Windows Live Local listings, as reported by SEW yesterday. It’s not clear how and when Microsoft will convert this into a pay-per-call model, but the move in this direction is significant for such a large online player and it could accelerate overall market adoption (Google has also experimented with click-to-call).

Although there is a great deal of business activity surrounding pay-per-call (and click-to-call) lately, it isn’t clear yet whether consumers are using it. Like many other new online technologies, there is an adoption curve. From a user perspective, however, it can be a functionally sound and efficient way to contact a business.

We’ll see how long it takes to reach mainstream status. When it does it will also be a powerful performance-based tool for advertisers to bring in qualified leads. Testimonials from SMEs suggest as much.