I have the Scott S40 and love it. Your selection all depends on what feels good to you. How did these bikes ride to you? Was the componetry equal? Whether its a Caad9, Allez or S30 buy the one that excites you and you know you will ride more.
All of the other misc items such as helmet, lock, etc can run you between 2-300. You don't need shoes and clipless pedals yet but I'm sure you will probaly want them sooner or later.