I second the suggestion to get Keynote if you are doing presentations.
For the rest of Office, you could take a look at NeoOffice/J (word processor/spreadsheet/presentation) and Abiword (word processor only). Those are free downloads off the net. Abiword is quite fast and handy. NeoOffice is slow to start up and lacks OS X look and feel, but has all office app types. Both will open MS Office documents well. Just get Office later if you find it's still worth it.
The idea to get a separate laptop for keeping in touch is shooting flies with a cannon. Not necessary. Two important questions here: what do you use Outlook for, e-mail, calendar, todo, anything else? Do you have an Exchange server at work or a regular e-mail server? If Exchange, that might force you to buy MS Office to get Entourage which I understand is compatible with Exchange. If regular mail server, then there probably are good Mac apps for anything you might be doing with Outlook.