I'm trying to do something I thought would be fairly easy (as I suspect I'm not the only wanting to do this) ;

For a given user that logs into SharePoint through the web services, list all documents available (I'm interested in documents from document repositories, but anything will do at this point). I'm getting increasingly lost in all the various ways into the maze, not being able to find a simple way to just get all those documents. Is there a way to search for them all, or get all lists of repository type (and their sub-sites of that type), or is there some obvious thing I'm missing here?

I don't have any technical problems, I get the web services fine, I can use them all, traverse items found and so forth, I just don't get the correct process to get to those golden nuggets. My thinking was to use lists.asmx -> getListCollection to get the main lists, and traverse those for documents, but that's obviously not how it works. I can pull out the list of Shared Documents (root) by name, but can I get a list of all repositories for a given user?