The middle part of this doesn't quite do what the OP asked for. I've
assumed the data is in Sheet1 columns A to C with a header row so the
data starts at A2. Insert a new worksheet and enter the following
formula in A2:

=Sheet1!A2&REPT(" ",19-LEN(Sheet1!A2))

In B2 you should enter the following formula:

=IF(Sheet1!B2<0,REPT("
",12-LEN(ABS(Sheet1!B2*100))-1)&ABS(Sheet1!B2*100)&"-",REPT("
",12-LEN(ABS(Sheet1!B2*100))-1)&ABS(Sheet1!B2*100)&" ")

And in C2 of Sheet 2 you should enter the following formula:

=REPT(" ",6-LEN(Sheet1!C2))&Sheet1!C2

I wasn't sure if you wanted three separate fields, or for them to be
joined together separated by a period. If the latter, you can enter the
following in cell D2:

=A2&"."&B2&"."&C2

Copy these formulae down for as many rows as you have data in Sheet 1.
You can fix the values by selecting all the cells, Click <copy> then
Edit | Paste Special | Values | OK and <esc>, then copy/paste into your
accounting package. Alternatively, you can drag Sheet2 away from the
main window and use File | Save As to give it a different name and a
format to suit your other package, eg csv or dbf, so that you could
then import it.

Hope this helps

Pete