Well Mush, I'd help yer mate if I had an address, but it is so easy it hardly seems worth the bother.

0. Create a blank movie-clip and press F5 on the timeline twice to give you three frames.
1. Put a textfield on the stage. Set it to "Dynamic" and set the variable to "scrolltext".
2. Create a new layer and in frame one of the new layer put the code:
scrolltext = "This is so piddly easy I am almost embarassed.";
3. Click on the timeline for the new layer at frame 3 and press F6 to give yourself a new keyframe.
4. In the new keyframe put the code:
scrolltext = scrolltext.substring(1, text.length)+scrolltext.substring(0, 1);
gotoAndPlay(2);

Drag the movie-clip onto the stage and see what happens when you test the movie.

All you need to do then is read-up on "loadVars" or similar and you are laughing like a laughing-boy who has been at the laughing gas too long.