Redzzz, do a search.
I doubt if anyone (who's not running a rental business and are insured) will be too willing to rent a premium, top-of-the-line lens. look at it this way, a single scratch or paint chip that probably won't affect the lens perfromance in any way will easily take a few hundred dollars off re-sale value. Would you be happy paying a few hundred dollars if the outside of the lens got scratched ... even if you didn't drop the lens? Or would you be willing to pay a hefty deposit?
Try contacting Dan (Trucatus here on CS). He has a wide range of Canon gear for rent, and he's a great and helpful guy to do business with. Another friendly renter I recall is Paradigm (IIRC). There are a few others like Jason as well.
All the best for your shoot.
