I use Google Apps with a custom domain. I have long found it frustrating that when I set up the account on my iPod Touch it only sets up the main calendar to be sync'd.
I have other calendars in that domain but the option to select or specify them never showed up.
I found that this is, in fact, doable.
On your device (iPhone or iPod Touch) go to:
http://m.google.com
Just follow the instructions from there.
