Privacy Fundimentals: LYING, PREVARICATING, PRETEXTING, FIBBING

Some people lie with breathtaking ease. Without a second thought. Without even realizing they're doing it. Sound like you? Then you'll have no difficulty executing an occasional fabrication of fact. But since privacy-seekers are generally honest people, some find this problematic.
If you deal with everybody with 100% honesty in all circumstances and situations, I salute you. You're probably an exceptional person. Most of us, however, compartmentalize to one degree or another. Lives are often composed of layers of complexity and nuance. We might be scrupulously honest with our boss regarding company-related matters, but will wing it as we see fit if the subject turns to our personal affairs.
Here's an ethical straddle that works for me: if you ask for personal information that is clearly none of your business, I reserve the right to lie to you. I could (and frequently do) flat-out tell you that it's none of your business, or I might answer your question with one of my own: "Why do you ask?" But there's often a time factor or a power imbalance involved that makes this awkward or impractical. At a given moment, I might lack either the time or inclination to explain that the cash purchase of flashlight batteries does not necessitate the logging and retention of my name, address and phone number. So sometimes it's easier to simply say "Elmer Fudd".
Although truth-telling is strictly your call, you are strongly advised never to falsify anything on a government document-- especially one containing a perjury warning. Never lie to a police officer. You do however, have the right to refuse to speak with them. If you find yourself under oath, you might want to take a cue from Jimmy Hoffa: plead the fifth.
Your decision to pursue a privacy lifestyle will likely meet with skepticism from family and friends. You're likely to hear things like, "But if you have nothing to hide, why should any of this concern you?" The reality is that everybody (even the person raising the objection) has something they'd prefer remain hidden. Something that would cause great embarrassment if revealed in tomorrow's newspaper. And that "something" probably has nothing to do with terrorism or criminal activities. You might decide to hide certain aspects of your business life, revelation of which could hurt your competitive advantage. You might choose to shield certain relationships or peccadilloes. If you're not hurting anybody or picking anybody's pocket, you have the right to keep these things hidden-- at least until such time as you get your own reality show.
Should you find yourself getting push-back from family and friends regarding your new privacy hobby, simply nod and smile smugly, safe in the knowledge that you're something of a pioneer, striking a blow for freedom. At worst, you're being civilly disobedient-- doing the wrong things for the right reasons. Like trespassers blocking entrance to some nuclear power plant, you're acting for the "greater good." If all else fails, explain you're taking a stand for the sake of "The Children." That gets 'em every time...