We very much regret that due to a change in the UK VAT rules, electronic or e-books are now subject to 20% sales tax.

This has taken place immediately on the Rowperfect shop.From HMRC website – paragraph 3

The supply of text by electronic transmission (including e-books), via the internet, or similar means is also standard-rated. Such supplies are of services, not of goods, and different VAT rules will apply to them (such as those on the place of supply of services – see Notice 741A Place of supply of services.