Currently digital download products are not taxed. However, if a bill is passed that taxes them, I'm just going to take a random guess and go with a 7% tax. I may be wrong though. If it was a 7% tax, then 26 *1.07=27.82 USD.
Actually I take that back, there is no tax if you buy it over the internet, but if you buy a gift card in the store then you will have to pay whatever your states sales tax is and possible a county or city sales tax also. It all depends on where you live so obviously we can't tell you what that would cost.
There is no tax, and no shipping either because you don't get a hard copy just a download.
Oh. Derp. But I believe atleast in the US the Congress IS debating a bill that taxes digital downloads.