Go to this page : http://downloads.maemo.org/

On the right orange search box select it to look for "IT OS 2007" applications

Hit the "Fetch" button (on the orange box on the right of your screen)

On the displayed screen, look down for "GNUMERIC SPREADSHEET" and then just hit on the
green arrow that says install. It will take care of it all, I just did that.

Hope this helps.