[xyclos]

Yeah, the second question is really important. What good is all the prep if you don't have an actual speaking engagement arranged?

And, you don't necessarily have to be "famous". One can keep an eye on conferences or other gatherings at which one would be interested in speaking. When they announce request for proposals, submit one. Spend a few weeks working on the request and make sure it is really well thought out and interesting.

when you get an opportunity to speak, take it (no matter how small). Speaking is a good way to build up that "fame" rather than the other way around.