Replacing a motherboard

After having to replace my laptop due to damage to the motherboard i now have an old laptop which apart from the mother board is ok. What i would like to know is can you buy replacement motherboards and if so how do you know which to buy. if i had the laptops manufacturer replace it, it is going to cost me over three hundred pounds. so i wondered if i could get one online cheeper.
The machine is a
Iridium Starbook 505-C90-CD Notebook
bought in Feb 2002
Intel Celeron 900mhz
630st chipset
Other than that im not sure what other info is needed.

Any ideas??????????
Stitch

 

Laptops are not as interchangeable as desktops. About all that might be able to use third party are the drives and RAM. Everything else is OEM only. You have to get one from the manufacturer or find the same in a junked same laptop.