found this free epub site should be able to download add to itunes and sync books www.epubbooks.com obviously its not going to have the latest books that you would pay for but hey it gives you a free option 
I agree that e book prices are high but it does say on the Kindle store that unlike print books, digital books are subject to VAT. Doesn't make sense to me but it's there.
The kindle store is not a global store. The available books and prices are different in the US kindle store and the international one.Apple are launching a service to compete with Amazon. Both readers are on the iPad. UK Users can click either icon.
Amazon chose to end run around local publisher nonsense by launching what is effectively a global store.
And Amazons dollar prices have no VAT. There is no VAT on books.
The iBook store only has a very short opportunity to put this right.
C.
The kindle store is not a global store. The available books and prices are different in the US kindle store and the international one.
Why would iBooks be any different?