In order to properly manage your promotions, you need to sort information by Country, City, Date of Last Purchase and Department.
This is easy with Google Docs. In the spreadsheet, click on the column heading by which you want to sort.

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Mouse over the solid dividing line which separates the headers from the data. When you do this, the bar will highlight and you'll see the word
sort and two sorting options. Select the option you want, and your data will realign itself based on your selection. Depending on the size of your spreadsheet, this may take a few minutes.
Another way to sort data is to use the Add Sheet function. Consider putting each department or country on it's own Sheet.
The next step is to export information so you can create email mailing lists, or mailing labels for physical mailing campaigns. We'll cover this in the next article.