Hi lenaros and welcome to Club Vaio.
Sony does not support XP on your model so there are no XP Drivers for the VGN-C2S.
The hardware on your model is identical to the VGN-C1 Series - except the C1-Series was sold with XP installed. You should be able to use all the XP Drivers and the XP Utilities for the C1-Series. Download the Original Drivers Package and the Original Utilities Package from here: -
http://support.vaio.sony.co.uk/downloads/updates/updates.asp?site=voe_en_GB_cons&c=0&s=VGN-C&m=2409
Remember that you will not receive any Sony Support and make sure you make at least two sets of Recovery Discs.
Updated links
The available drivers can be found on the support pages for your model here: -
http://www.sony.co.uk/support/en/content/cnt-dwnl/VGN-C2S/list#os4
However, the previous model - the VGN-C1S, does have a full set of Drivers and Utilities for XP and these probably will work with your Vaio. Full downloads are available here: -
http://www.sony.co.uk/support/en/content/cnt-dwnl/VGN-C1S/list#os4
Good Luck
