You'll know when the booklist comes out on August 17.
In past years, it has been the good old "Organic Chemistry" by Solomons & Fryhle + any molecular model kit (not mandatory but most students find it very useful).
However, I would definitely advise against purchasing course materials before the booklists come out. Many people don't buy until they've been to their first class because some profs make changes to what is required/what is optional, etc.
EDIT: Ahh I posted at the same time. Oh well...I'll keep my post