You can't set it for an entire workbook, so far as I know, SB, but you can make it a cell format, and apply it to all of your appropriate cells.
Hold on, let me pull up Excel.........
Whichever version you're using, pick a cell where this will apply and go to "Format cell -> Numbers".
Choose a normal currency, and set your parameters of using a thousands separator and how many decimal places you want to use, then click OK.
Now return to "Format cells -> Numbers", and select custom. The format will load in the "Type" box.
Replace the regular currency symbol with "Cr" (no quotes), then click OK. (It will put a "\" between the C and the r for some reason in the format, but that won't show up in your cell.)
If you want the symbol on the other side, simply type it there when you do the replacement of the regular currency symbol.
Now, any time you want to apply it within that workbook, simply highlight the appropriate cells, and apply that custom (it will be at the bottom of the list) format.
It will look like this: C\r#,##0.00