If it's a so-called clickpad (which I assume it is, since those are now on about 95% of laptops), then you most likely just need to run synclient to set up a region at the bottom of the clickpad that you want to behave as the RMB.
I have a script that runs when KDE starts which contains:
Code:
synclient BottomEdge=4500
synclient MiddleButtonAreaLeft=2965
synclient MiddleButtonAreaRight=4164
synclient RightButtonAreaLeft=4165
synclient RightButtonAreaRight=5765
This sets up a region where clicks will be interpreted as a middle button and a right button. You'll probably need to use different values depending on your specific touchpad.
Dave