How can you tell if an ebook is available in a Kindle format? When you go to our ebook service at http://alliance.lib.overdrive.com :
1. You can click the blue “library ebooks for Kindle” button on the left to search for everything that is available for Kindle
2. You can do a regular search and if the copy can be checked out by a Kindle, there will be an option in the format section.
More information from Overdrive on how to use Kindle books at http://overdriveblogs.com/library/2011/09/21/library-ebooks-now-available-for-amazon%C2%AE-kindle/
2nd UPDATE 9/26/11
The Metropolitan Library in Oklahoma has a nice Q&A page on using the Kindle with the library's ebooks. It's available at http://www.metrolibrary.org/kindle/