Madeline Mann.

It took me a while to warm up to Madeline. The first few chapters were hard, and the first time I read them I gave up. But then I ran out of Julia Buckley books to read, having recently re-read the Undercover Dish books, the Hungarian tea shop books, and the Writer's Apprentice books. So I tried again and grew to like her by about halfway through the book.

I haven't checked the pub dates, but I think these must be an earlier series - the writing feels less nuanced, but it was still a good story, with good clues and red herrings too.