I setup the plotter in the program but I have found out that I don't have a gspplott function available. It's like I have to call gerber and get them to tell me how to install the gsp. I have installed all software and driver updates that gerber has provided and still have no control of the output function in composer.
Look in your Programs menu for a Gerber Group and see if the program GSPPlot is in the list. Also, have you ever had any plotter driven from your copy of Omega. If not, it is possible that you have a Layout version of Omega which does not include GSPPlot. Plot should appear in the System ID list (accessible by right clicking on the GSP Tray icon) for you to have a version capable of driving a plotter.
If you do have GSPPlot, open it, then open any saved PLT file you may have, and enter function key F7 to open the Device Select section. Look to see if any plotter is shown as being available. If your non-Gerber plotter is not installed, you can try to install it as an HPGL plotter and see then if you can get it connected.
If this is a used copy of Omega that you bought from a private party, you may well be screwed. If you bought it from a Gerber distributor, you should consider asking them for help.