At least my EeePC 1101HA came with a pre-installed trial version of Microsoft Office. It turned out to be nagware so I uninstalled it almost immediately and replaced it with a free alternative, OpenOffice.org. I haven't tried if Excel macros work at all with it but other than that it should fulfill all your office suite needs. It doesn't even feature the stupid ribbon-interface that the newest versions of Microsoft Office have.
Of course, if you have always got an internet access available you might as well keep your documents online. For that I recommend Google Docs. It is really nice to be able to access your documents from any computer with an internet connection. You can also share your documents, spreadsheets and presentations to others for collaboration. Import and export to and from the most popular formats are available too.