I do this with Notepad++
(Note this method works regardless of the version of Excel/Office you have.)

1. Save your work using File => "Save As" and select "CSV-UTF-8" as the file save type.
   (This is important, especially if your spreadsheet has non-English characters.)

2. Open the .csv file in Notepad++

3. Have fun with your regex replacements and save when done.

4. Select the saved .csv file and "Open With" Excel.
   You might have to adjust the column widths and/or row heights, but it's much faster to do it that way than in Excel.

(Side note:)
One of the things I do with my data-conversion spreadsheets is, (after I get the data reasonably normalized, (like data in the same columns, etc.), I create a new first column and use the shift-drag feature to put an "index" in the first column starting with 1 so that I can keep track of the lines, and re-sort them if needed. (My European bank statements come sorted latest to earliest and my financial software wants things sorted earliest to latest.)