A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
You are correct, there is no easy way to filter the files as can be done under windows. There are, however, many problems with getopenfilename on the Mac. It has been a long and often reported bug (by me) that it often returns an incomplete path. This problem has been around since maybe forever, (at least since before Excel 2004) and has apparently not been deemed important enough to fix. The basic problem is that if the user uses the disclosure triangles to expose files in a folder, the entire path is not returned. If the folders are double clicked instead, the path is correct.