There's a native port of Open Office called Neo Office, which looks a little prettier and is as equally free. These can both save to a variety of .doc/.docx standards from different office editions. You're very unlikely to have any compatibility issues but it's reassuring to have a copy of word etc. if it's an important document so you need to check that it's perfect!
another option is this LaCie 500GB USB2 drive for £65:
on amazon search LaCie, Desktop Drive , Design by F.A Porsche, 500GB, 7200RPM, USB2, Mac and PC, Plug and Play (can't post URL - too few posts!)
bargain!
If anyone is still looking for a copy then ebgames.com have some copies it ends up being about £33 incl. postage to the UK - I think this will be my option!