Madison Avenue has joined forces with Internet companies in a last-ditch attempt to stop privacy regulations over the $29 billion online-ad industry, reported The Wall Street Journal.

The industry is finalizing an ad campaign to educate consumers about how digital advertising works, creating an icon that would appear on Web pages or ads alerting consumers if their activity is being tracked and deploying new technologies to police the Web for illegal activities. At issue is the practice of tracking consumers’ Web activities — from the searches they make to the sites they visit and the products they buy — for the purpose of targeting ads.

The efforts follow calls from the FTC earlier this year for Web advertisers and Internet companies to do a better job explaining how they track and use information about consumers’ Web activities and creating a simple way consumers can opt out of being tracked.

Meanwhile, scrutiny in Washington continues to build. Lawmakers and regulators have broadened their scope beyond the Internet and are starting to examine privacy practices for a wider swath of media and technologies, from mobile phones and newfangled interactive TV commercials to telephone pitches and the advertisements consumers receive in their mailboxes.

The Future of Privacy Forum, a privacy group backed by AT&T, is in the final stages of developing a logo that would appear on ads or Web sites to alert consumers to customized ads or that their Internet browsing is being tracked. The goal is to create a symbol that will gain the same awareness as the recycle triangle, says Jules Polonetsky, director of the forum. The group has yet to settle on a particular logo but has nixed using a “T” for targeting or an eyeball.

Some industry players are ramping up their own efforts. Yahoo, for instance, has started testing several ways to try to make the tracking on its sites more transparent. In one example, an eBay ad on its Yahoo Green site includes a box labeled “AD INFO” in the top right corner. Clicking on the box reveals details about how the ad appeared on the page, including who the advertiser is and that Yahoo customized the ad based on past online activity. It also provides links for consumers to opt out or learn more about privacy and online ad targeting.

Yahoo’s events site includes an “about our ads” link at the bottom of the page that takes consumer to a Web site where they can learn more about how ads are customized according to a person’s Web browsing and choose to opt out of the tracking.

Other companies are cropping up to provide technology for advertisers to audit their online advertising and check to make sure it is in compliance with regulatory guidelines. Former About.com CEO Scott Meyer recently launched a company called the Better Advertising Project that provides a technology for marketers to use to monitor their online ad campaigns.

Lawmakers and regulators say they are closely watching these developments. “If the industry doesn’t step up to the plate with vigorous and consistent self-regulation, they are inviting a more regulatory approach,” FTC Chairman Jon Leibowitz said in a recent interview.