digitalpaintartist Have you looked on thebookpeople.com for book ideas?
They often have sets of books that are good - and if you sign up to their email list or watch on these threads, they often have offers or sales of some sort so don't ever buy from them without getting some sort of a discount!
I have ds rather than dd so not really into girls books. And not sure what her exact age is - somewhere between 7 and 9 I'm assuming if she likes David Walliams.
Guessing she will already have got Roald Dahl books - they're always a good bet if not, and they're currently £22 a set of 15 books on Book People (with money off if you spend over £30 or £40)
They also have a David Walliams collection if she hasn't already got them, a Mary Poppins collection, all sorts of things by less well known authors but around a theme if she likes something like princesses or creatures etc. Even something like the Wimpy Kid or Michael Morpugo?
Then there's things like learning to draw books or factual books or Where's Wally for something very different?
And finally - there are lego Friends books if the lego friends set is also for her - could tie the book and present together?