I've not done this...but I've installed windows on many-a-PC/laptop enough to know the following:
1. Download the XP Drivers for the netbook from =>
http://www.elonex.com/support/products/webbookxp.shtm (on right hand side menu), and place them on a USB Stick.
2.Get a USB CD/DVD-ROM Drive (beg, borrow or buy).
3. Plug in said USB CD/DVDROM and put Windows CD/DVD in drive
4. Reboot and tell netbook to boot from CD/DVD Drive (button combo depends on device, check manufacturers handbook)
5. Follow on screen instructions to install windows, remember to format the HDD (which will wipe linux from it)
6. Once windows boots, install drivers
That should be it.
If you aren't confident in doing all of this, I would advise finding a friend who is confident in installing windows, and get them to do it for you, or alternatively, take it to an independent component dealer (they will charge approx £50 for this I reckon).