Like Vin, I'm generally too linear for mindmaps. That and I never seem to start with a big enough piece of paper.

I think in sentences, not fragments, and I HATE to miss a thought. So my little branches are more like thick paragraphs all over the place.
I have a very strong hand/brain connection, so I usually start by writing notes down by hand and going off the notes. I often start a letter by writing some bullets (helps me uncover hidden points, including things that can be turned into a headline or subhead), then taking my notes and turning them into the roughest of rough outlines. Then I just work on the pieces-parts. I wish I was one of those "write the headline first" people, but alas, I'm just not.
I am a self-indulgent nerd when it comes to old-skool tools, so, despite the fact that I go through reams of them, I take notes on the spendy, creamy, altogether heavy Levenger letter pads.