The green book in the bottom left is ‘Nanny Piggins and the Rival Ringmaster’ (book 5). Book 4 is also available. It has a blue cover and is called ‘Nanny Piggins and the Accidental Blast-Off.  They are now in the US book distribution centres, which means your local bookstore can order a copy for you! Or you can order one from an online seller.  Here’s a couple of links…

Nanny Piggins at Amazon.com

Barnes & Nobel has them too…

Nanny Piggins at B&N

And in even better news books 6 and 7 in the series will be availabe from November.