iTunes card offers seem to be quite thin on the ground at the moment, which is why the $40 for $30 offer at Target, which starts tomorrow, is about the best deal out there at the moment.
This offer starts on the 30th of May - tomorrow - and runs until 12 June.
I'd say these make great birthday or Christmas gifts, but it may be a bit early to mention the "C" word - that said, if you're able to save some money why not? Just double check that they wont expire before then, but they definitely shouldn't!
There's not a huge amount more information about this offer, but what more do you want to know? It's iTunes gift cards. There's 25% off. It starts tomorrow.