Greetingz!
Well, most Americans seem to use Facebook for some reason. But if you want something less...public.
You could try just setting up a Wordpress blog. With the right configuration, it would be kept away from prying eyes.
However, if you want something that's more private then you're going to have to either;
a) Setup a Linux system with whole-disk encryption, then just use SeaMonkey.
b) Use a text-editor and GPG.
Of course, I would recommend going with one of the online options, just be sure to "Change the names to protect the innocent".