Can anyone recommend a good book that I can buy to learn how to write
macros in Office? 2004?
I'd recommend John Walkenbach's "Excel 200x Power Programming with VBA".
You can get the 2003 version, but the 2002 and 2000 versions will do
fine, and may be available cheaper.
90% of the earlier books, and 85% of the 2003 version are applicable to
MacXL. You'll need to make adjustments (e.g., MacXL is at VBA5 while
XL00-03 use VBA6), but it shouldn't be too difficult.