In response to my previous article about joining data from a csv file, I received a very good tip. From QGIS 1.8 Excel files can be opened directly in QGIS. Strange enough, nothing is mentioned about this in the ‘release notes’. It only works with the older XLS-format, not with the newer XLSX format.
You can open an Excel file with the menu option or button ‘Add new vector layer’. That is confusing for non-spatial data. Your Excel file should contain a column to be used to join both layers. Further, you need one or more columns with the data you want to display. Co-ordinates are not required. Set the file type filter to ‘All files’. Otherwise your Excel-file will not be visible. The dialog doesn’t contain a special filter for Excel files.
If all went well, you can now join the table to a spatial layer, like described in my previous article.