Geoff Watts was in Oslo a while back giving a talk on how British Telecom introduced Scrum to the organisation. Important elements in his talk was how to motivate, and how to let experience gained in some teams propagate to other teams. To summarize in short it was by stating the goal instead of how to do it (deliver something every 90 days), and have experienced coaches come in and lecture but also participate in the new teams that are just started and trying to find their way.
Similar and more specific ideas can be found in the slides Jeff Sutherland did at Google. I would love to hear the talk, but the slides gives a lot of interesting information on how they introduce new teams to Scrum at MySpace. Some of it seems a bit harsh, but I do actually believe some teams needs a painful bootstrap to get into it.