Blackberry 8300 eBooks are in the Mobipocket format. Easy to install and use.
Blackberry 8310 eBooks are in the Mobipocket format. You can find a ton to buy at eBookMall.com.
Blackberry 8320 eBooks are in the Mobipocket format. Great selection available.
eBooks for Devices -- Smartphones, Palms, Pocket PCs, Blackberry