MacRumors administrator, Doctor Q, has done some research in finding opt out links to get off of certain mailing and calling lists. I think its great information to have and can be difficult to find at times. Therefore, I am re-posting it here for the benefit of all.
I routine opt-out of mailing lists, cookie trackers, mobile phone trackers, and other collection systems would otherwise track me without my permission. But I don't click on any old opt-out link since unscrupulous people could collect personal information that way. The services I opt out from are the ones I know to be legitimate tracking services that collect information and sell it to other businesses.
Here are three of them. Since these services are pervasive but obscure I thought I'd share the links I uncovered with you. If you know more real tracking businesses from which we can opt out, you're welcome to share the links.
To opt out of their unsolicited phone calls, snail mail, and email, you have to go through a convoluted process starting at this page.
For an opt-out cookie, go to this hard-to-find page.
For an opt-out cookie, go to this page.
They track your phone's WiFi information when you go into certain retail stores.
To opt out you go to this page and enter your phone's MAC address (Settings -> General -> About -> Wi-Fi Address on your iPhone).
If you use a cookie manager, you need to mark any opt-out cookies as "permanent" or "whitelisted".
There was a recent Security Now episode (Security Now 404: How Facebook Monetizes) where Steve Gibson spoke about those companies as well. He detailed how they work and ways to opt-out.
Download the pdf version with pictures here.