For me, the acceptable price depends on the book and the author. I have a couple of auto-buy authors that I will pay up to $12.99 for the ebook. On the other hand, there are at least 10 more that used to be auto-buy authors until agency pricing went into effect. Now their books are still on my wishlist until they get to paperback price levels. I could buy the hardbacks on the discount book table for about $5.00, but don't want more hardback fiction books cluttering up the house. The upside is I have been making my way through the giant TBR pile I aquired during Fictionwise's heyday.