Why do Buddhists believe there is no creator?

Why do Buddhists believe there is no creator? Do Buddhists in general also believe there is no supreme being, or do they settle on that there is no intervening supreme being? Are these the Buddha's thoughts or a deductive conclusion from some type of logical reasoning? If they are mainly the Buddha's, how come they are generally accepted - as far as I understand it, he encouraged everyone to not take his word for anything, but instead seek the truth for themselves? As you understand I'm a total Buddhist noob, please correct me where I'm wrong and clarify where needed!