So, the real challenge you face with an Aesop Storybook is figuring out just which stories you will use (fables about a particular animal or other character? or fables that emphasize a particular theme?) and what strategies you will use to re-tell them in your own words. You can probably get some good ideas by browsing through these Aesop Storybooks from past semesters.
Online Fables. You can get some good background about Aesop and the fables in the Aesop unit at the Myth-Folklore website. There are also lots of Aesop fable collections online, including both translations from the ancient Greek and Latin sources, as well as modern retellings. If you want to read the actual translations from Greek and Latin, you can find 600 Aesop's fables, arranged thematically at the Aesopica.net website ... yes, those are my translations! The Aesopica.net also has an index so you can search for fables by animal. For modern retellings, including the famous fables of the French poet La Fontaine, see the Aesop's fable section on the Greco-Roman book page.
Aesop Illustrations. For illustrations to Aesop's fable, you can find literally hundreds of illustrations at this Flickr collection of Aesop illustrations ... yes, that is my Flickr collection!
As you can see, I am kind of obsessed with Aesop's fables and have been for many years, and I never get tired of reading about the fables told in new ways. :-)
Here is the fable of the fox and the crane, as illustrated by Walter Crane (full-size view):