Does it run from a database? If so you could probably export it, though it might not be as simple as reading the items in an excel spreadsheet. You will probably find that it's a relational database and a little more complex than a single page spreadsheet.
If all you want is a backup then there should be something in the admin section that allows this?
Do you know the name of the package you are using?
How to watch Wimbledon 2015 live online: follow the tennis from your laptop or PC