Startup Menu

I'm a Mac newbie.
I downloaded a demo,which has since expired.
On startup it asks me to register&buy.
I thought I deleted the small program,but I see it on startup after every bootup.
It was easy on Windows,but don;t know to delete it on my Mac.
Any help is appreciated.Thank you.

Have you removed it from your /Applications folder? If you have, something must still be installed.

To disable it as a startup item, go to System Preferences > Accounts > click your user > Login Items > highlight it > click remove button (- button below the list).