Additional startup screen made easy?

I need to create an additional start up screen either before or after the login screen. I need to put in our Company’s disclaimer message and a functional OK button so that the user has to select the OK button to move to the next window.

I know you can easily add additional copy in the log in window with third party applications but I need a separate screen with a OK button. Apple pointed me to the Developer Tools but I am not a programmer and don’t have the time to invest in learning these applications for this one time project.

Does anyone know of a tool preferably with a GUI or have a process by which I could accomplish this? My project leader is more then happy to keep pointing out how easily this can be done on a PC and I can’t believe we are the first company that needed something like this. Thanks for any help!

Jeff