Many thanks, Tony. I had been looking under the Styles files, not indents.There is a very useful page at http://www.gcflearnfree.org/word2007/21.3 etc.
BUT it doesn't tell me how to incorporate it into the default style. Have you any ideas?
You would probably need to set up a blank Template with all the settings you require for that particular Document if you are using it a lot. Something akin to the normal Blank Document Template, but set the way you want it and then saved with a name relevant to the end use.