Subject:
Free Macintosh Spreadsheets
Free Spreadsheets software download for mac os x
The following is one of the best free items:
NeoOffice Home
OpenOffice.org - The Free and Open Productivity Suite
Appears to be good, but I never tested it:
GNOME Office / Gnumeric - Downloading Gnumeric

Just Spreadsheets: Simple, good, and for the average user, non-business use.
BC Spreadsheet - Mac Free

List of free spreadsheets:
Spreadsheet Software - Business Software - Mac - Free Software Downloads - ZDNet Asia

Question:
What model do you have. Must be from the year 2000 or before.
The Power Book 100 came with a floppy, but no internal drive.
Some people added an internal drive.
See the article listing:
Macintosh: Support for External Floppy Drives
Note: Although MS Office programs are cross platform, the pure Mac products may not be. They can only be used on a Mac.