I've never been a fan of Audible's contract stuff. I'm only interested in unabridged too. I like
Blackstone Audio. And I check
Book Closeouts once in a while to see if they have anything in worthwhile. I've found a few nice things very cheap.
I also like
W F Howe which is where I found audiobooks of Dorothy Dunnett who I consider one of the two greatest writers of historical fiction. And the other writer is Patrick O'Brian and I found his audio books at
Isis Publishing. Both stores have many other authors obviously
Oh and they have a few at Buy.com, which is particularly good if you catch a sale.