Should be able to add to your home directory to a file called ' .xinitrc '. Here is an example of mine.
The ' & ' symbol is required to release the program from that session. If you don't have one then create it. If you create one then make it execuable with this command. ' chmod +x .xinitrc '
If you use KDE a link can be placed in your home .kde/Autostart.
" Google the Linux way @ http://www.google.com/linux