Linux On My Samsung

please help im a noob, have no idea how to run the many scripts i have seen on many websites. my n150 has lost brightness control and fn keys do not work. this happened after i isntalled ubuntu 10.04. i can adjust brightness on boot but as you probably know this is not a good way cause i cant control the optimum britghtness i want.

how do i fix this problem and please take me step by step...i have printed some scripts but have no idea where to enetr them

where do i find this :/usr/local/sbin/backlight