I have an image from Google Earth of part of the New Zealand back country. I want to draw a hiking/tramping route (I'm thinking of a red line) onto this image as it is being described in words, so that the route line starts off and progresses as the story is told over a sentence or two..

I'm not sure how to go about this. Is there an easy way to do it?

Method #1. Use two images, one plain and the other with the line on it that you drew in something like Photoshop and then do a wipe between the two.
Method #2. Try a free app called Route Generator. I've never used it but have read of a few Vegas users using and liking it.
Route Generator (http://www.routegenerator.net/)

Thanks Mike. That is exactly what I was after...it looks great and is very easy...

But Vegas doesn't recognise the output media file...so I'll have to drop in all of the individual files to get the sequence...which is actually better as I can start and stop the line easily that way...