ok.. let me try to guide you. you want to run afterstep in linux bcoz u are used to running litestep in windows. ok that makes sense to me.
from the above link you can install afterstep. if you have already installed apt. apt-get install afterstep will do it for you,
after restart x by pressing ctrl alt and backspace. check if you have afterstep in the session list. if not you might have to add it manually. that depends on whether you are using the gnome display manager or some other thing. the default one with redhat 9 is gnome display manager. you can use the gdm help to figure out how to do it.
if you like build from souce
go to afterstep.org and download the it.. the third icon in the list. and follow the readme. i guess you wouldnt like this option
i havent installed afterstep myself. so if you have any specific problems post back and i will try to help you