How To Create a Hyperlink to SharePoint's List Export to Spreadsheet
Replace the [Placeholders] with your environment's information. A handy way to get the list and view GUIDs is to go into "Modify Columns and Settings" then scoll down to the views section and click on the view that you want to use. You will notice the escaped list and view GUIDs in the resultant URL.
Here is an example:http://MyWSS/sites/samplesite/_vti_bin/owssvr.dll?CS=109&Using=_layouts/query.iqy&List=%7BD109453A%2D1A6E%2D4F83%2DAFF9%2DCCA04A75D76D%7D&View=%7B8FB21A2F%2DB62C%2D41D8%2DBA0C%2D7BD9C31FAA51%7D&CacheControl=1
See also, MSDN's article: URL Protocol and my article: How To Add a Hyperlink To a SharePoint Event Outlook Export