This is the kind of reply I consistently get from Fictionwise when I ask about their prices (which I've done on probably three separate occasions) -- they always say the publisher sets the price and I need to talk to the publisher. I've sent several e-mails to a bunch of publishers and have never received any sort of reply, which I find really irritating.
I also happen to have a good friend who is an author published by Ace, and her books have recently come out as ebooks. (Shameless plug: Moira Moore - start with "Resenting the Hero"

) Anyway, they put out books one and three first and they priced them at almost double the paperback price. I told her about it, she contacted her editor, and within a couple of weeks, the prices had dropped down to normal cost ($7.99 not including any discounts). About 2 weeks ago, they released book 2 at $12.99. I let her know -- she's really annoyed btw -- but so far, the price hasn't changed.
Anyway, I don't really know what all this means except that it seems like you need to know someone in order to get anything fixed, but sometimes even that doesn't work. I would love to get some sort of petition or something together to send to the publishers that are the worst offenders (*coughMacmillancough*) and try to get them to knock it off. It drives me absolutely bonkers.