The falling tone you mention I consider quite British, actually. In AmE I think we tend to have a rising tone there. In the case of bisyllabic bookstore, with primary stress on book, the whole word has 'rising' intonation insofar as book has a low tone, and store a high tone, regardless of please (which has the same high tone as store):Yes, wh-questions have falling tone on the stressed syllable of the last main word (\book-). A following phrase not essential to the meaning has rising tone:
Where can I find a \bookstore, /please?