Web directory: /home/username/www
Replace username with the cpanel username for the account the script is under. The previous 3 paths may be asked for in the script as an absolute path or a system path. Please note that the paths only go as far as the directories above and you may need to add on to them for the specific file or directory your script is calling for.
You can also find your paths when in cPanel - on the left hand side at the very bottom of the page.