So far my tests and Googling have failed. I'm using the Large ResponseGroup to get info on Kindle ebooks, and there is no price of any kind in it.
How cna I consistently get a price on ebooks from the Amazon API? Is there a particular ResponseGroup that does it? I've tried Offers, OfferFull, Variations, you name it.
I know that Kindle ebooks don't have Offer pricing in the API. I tried it anyway, just in case. I'm looking for any price at all at this point.
Alright - info on this is very sketchy, but I have a best-guess at why there's no price associated with ebooks through the Product API.
Amazon don't allow any of the usual Offer ResponseGroups, they cut that out a while back. Although the list price SHOULD be available, Kindle books don't seem to have one to start with - they have a Kindle price which isn't provided, as far as I can tell.
So far I've tried ItemSearch with a SearchIndex = KindleStore, ItemLookup by ASIN, and I've gone through most of the more likely ResponseGroups in order to find any price associated with a Kindle ebook, and there is no sign of one in any combination. At this point, I'm going to assume that ebook prices are not available at all through the API for unknown reasons at this time.
So the only way to get it is by using a scraper and risking Jeff Bezos' wrath.