Find "NULL" values

[mdmarsh]

Hi. I am trying to upload the data from an excel spreadsheet I've created into a MySQL database created by a programmer in phpMyAdmin. The programmer has told me that "NULL" values cause problems with the upload. He says "NULL" values are not "" values in a cell or blank cells and that I need to find any cell with a "NULL" value in it and place a space in it before I upload. Any ideas on how to find those "NULL" values? I need this to be simple b/c I have to do the upload 8-9 times a week. Thanks!