For me it depends on who I'm talking to. I don't give out my information to everyone because it's of no concern to everyone where I am from. But even if I do tell the person where I'm from, I don't give much detail in my answer. If someone begins asking for my name, well, that is something they have no need for and that is when I choose one of my other "identities", each of which has its own name, postal code, age, background info, etc... .

Something such as MySpace or FaceBook, those I don't use as I feel those aren't exactly trustworthy sites for me to give information to or put up pictures of myself or others.