Applet for really, really basic pathfinding?

I need to do an entrance path for something I could best describe as a 3D Galaga. If you remember how the enemies entered the Galaga screen in swooping path, usually with a little run around a circle before hitting their position in the formation, its effectively that, but in 3D. I realize there are lots of papers on complicated pathfinding, but this is so basic I assume there's a shortcut. Ideally a little applet where I can draw a curve and it would spew out a table of X,Y,Z coords would be all I need. Before I write something myself, could anyone point me at an existing solution? Thanks! - Dave