Any valid user on your server has access to the statistics generated by Webalizer.
The URL is: http://anydomainonyourserver.tld/stats/
Webalizer makes use of a CRON-job, to update the statistics every day.
Login into your server as root.
Enter the command: crontab -e
Now you see all the CRON-jobs, which are running on your server.
For webalizer you should have a line like this:
0 4 * * * /root/ispconfig/php/php /root/ispconfig/scripts/shell/webalizer.php &> /dev/null
This means that the webalizer statistics are updated every day at 4:00 am.