On Linux there are cron jobs for users setup pretty much the same way as they are in UNIX. You can see those files in /var/spool/cron. The user that owns the file is the user the commands within it are run as. The files are ascii files so you can cat them to see their contents.
Also you can use "crontab -l" as a given user to see that user's cron (e.g. if you are root crontab -l will show you root's crontab). Also if you are root you can see other people's crontabs by running "crontab -l -u <user>".
Unlike UNIX, Linux also has special cron for hourly, weekly, daily and monthly. These files can be found in /etc (ls -ld /etc/cron*).
The script you're looking for is likely in one of those but it is possible that one of those is running something that is in turn running the script you're looking for so you may need to go through the scripts you find to see exactly what they're doing.
You can get more detail on cron by viewing manual pages with "man cron" and "man crontab" commands.