Yes, I do. What does the disbelief in a god have to do with morality?
There are many differing views of morality and its nature, and I'll briefly touch on them later in this post, but I will to first convey the fact that our morality (at least the crude part of it) came from the process of natural selection, as genes that promoted the killing, or theft of property from fellow organisms within a community would have had adverse effects (e.g. a community in which murder is accepted as an acceptable practice would not survive, as the death rate would far exceed the birth rate), and genes which promoted what we would now consider ethical behavior would result in the prolonged existence of each organism as an individual, as it encourages them to work together in their struggle for existence.
With this extremely unrefined morality in place, many actions that we would not think of as acceptable today were also treated as taboo. Such actions would include actions such as rape, theft, and murder.
Now, this is not to say that any of these primitive ideas reflected our modern ideas regarding the topics; for example, in some rival clans of humans, it was perfectly acceptable to kill each other (that is, to kill members of the rival clan) and this was not treated as such an impermissible action, as you weren't going against one of your fellow clansmen. Because today, we don't allow such divisions to exist between ourselves (at least not to the scale of this time), murder is universally accepted as wrong. In these ancient times, while rape was seen as a negative thing, it was not understood that women have the same worth as men, that is, they are just as capable intellectually, and (almost) physically (men have a slight biological advantage over women physically, but this cannot constitute a reasonable cause for making rape permissible), so that rape was seen in a far less negative light then it is today.
As time progressed and people employed reason, they attempted to find an ethical code on which we can base our morality [this was the beginning of moral philosophy]. Many different ideas exist on this, which range from consequentialism, which postulates that the end justifies the means; utilitarianism, being a more general variant of consequentialism, which advocates the idea that the moral worth of an action is determined by its utility in creating happiness. Yet others exist, such as moral absolutism, which is the view that certain actions are right or wrong, regardless of the consequences of such an action, implementations of which are classical liberalism, modern libertarianism, etc.
Regardless of what ideas one specifically adheres to, it is quite clear that one can (in one's own way) judge what actions are moral and immoral without relying on the judgment of an ancient text which condemns witches and homosexuals to death. Such is the nature of moral progress.
Now, let me ask you a question. Why do you have to ask people who disbelieve in the existence of a deity if they think morality exists?
Below is a video in which Richard Dawkins addresses this very issue.
[YOUTUBE]zSYosM2ZhzY[/YOUTUBE]