I am not sure if there is anything called "Computer" in Red Hat Linux 9.
Any way, this is what I would do if I wanted to add a programme on desktop.
Lets' say I wanted to add "Control Centre" on desktop.(this looks similar to "Computer" on fedora)
1. Right Click on desktop.
2. Choose "New Launcher".
3. Once the window opens, put "Control Centre" on Name field and "gnome-control-center" on command field.
4. You can select some icon clicking the "NO icon" button if you like.
5 Press OK.
(If you are not sure about the command of the application you like to run, just goto menu, go the application you like to run, right click on it and choose properites. Then you will see the "command")
It will not harm if you play with this for a while. This will make it bit clearer.
Hope this answers your question.