Toshiba usually provide a Windows utility to make a set of factory recovery discs. It'll be in a "Toshiba" folder in Start > All Programs.
Or you can invoke the built-in Factory Recovery process (provided the recovery partition on the hard drive is still intact) by keeping the 0 (zero) key pressed as soon as you turn your laptop on.
Failing that, you can order a set of recovery discs from Toshiba for certain models.
For Europe, the ordering page is here: http://backupmedia.toshiba.eu/