I know that software can be expensive, especially for complex or business-oriented packages. However, there are some excellent free programs that do what the expensive stuff does.
There are also cloud services, where you use software over the Internet.
Google Drive is great for wordprocessing, making presentations, and spreadsheets, just like Office is.
Dropbox is a way to share files and folders with your colleagues.
And of course, if you need a cheap computer to run it all, check out Free Geek Vancouver.