JMNSHO...

If you give them the book, they won't want the training. :)

I'd concentrate more on a catchy pull-line. What you have now is not a hooker in any sense.

I'd put 'Perl Training * Australia' on one line along the bottom with the fine print below it, and concentrate on doing something very funny with the main mug space. Maybe a 'roo with a camel's head popping out of the pouch?

Useful (OTT holding hot liquids) is not what mugs are for. They're cultural statements. :D