Normally drivers only can be received from the manufacturer of the laptop. Unfortunately only a few manufacturers maintain the drivers for all their models. Updates can be received only in the case of eliminaion of a serious lack. For some hardware, which is inserted into many notebooks, there exist reference drivers.

Here is a list of frequently incorporated hardware, to which there exist updates from the manufacturers:

Video Chip: ATI has own mobile drivers (however only for some X700 and X800), Nvidia and other ATI grafic chips can only be modified by the following "Mods" in such a way that they run:
ATI:
omegadrivers
mobilemod (im rage3d.com Forum)
NVidia:
LaptopVideo2go.com
Tip: Sometimes the drivers must updated manually in the equipment manager, because the provided setup programs do not function.
Under Linux almost all video card drivers function with the mobile correspondent cards.

Touchpad: The origin of most incorporated Touchpads is Synaptics. From their site drivers also can be down-loaded.

Intel Centrino Downloads: For WLAN, chip set and processor current drivers can be found here.