Flash Button Scripts

Hi there, Im totaly new to this forum, but Im hopin I can get some help with a little prob I have. I am close to putting my site live but have a couple details that i wish to look at.

In my portfolio section i have standard rollover buttons that tell target, and load external movies and .txt docs, which is all fine but i have seen buttons that have an over state which remains over once the user has clicked the button, to show which ones they have clicked.

Does anybody no of any script that will do this?

Hope you can help.
Cheers