Are you running Ubuntu and trying create a cron job, and everywhere you look you see the command crontab, but command not found is all you get when you try to use it? Yeah, that one never stumped me either 😉
I’m was working on setting up a cron so that I can email blog posts into django-articles (gotta love this app), and everywhere I look it mentions crontab. Took me a while to figure it out, but it turns out that the command crontab is installed with package cron–at least on Ubuntu. So if you are missing this command, do an sudo aptitude install cron and then you should have your crontab command.
I hope this saves someone a little time and frustration. I know I was surprised that it took me so long to find out which package this command belonged to (I thought it was its own package actually, so that slowed me down a bit).