http://support.euro.dell.com/support/topics/topic.aspx/emea/shared/support/dellcare/en/byphone_ord?c=uk&l=en&s=gen

or here

http://support.euro.dell.com/support/topics/topic.aspx/emea/shared/support/dellcare/en/contact_us_options?c=uk&l=en&s=gen&~tab=1

If you intend to use WXP CD for repair of OEM (Dell) installed OS, note the warning in MS KB article 307545

Slightly different problem, but similar issue read this thread, click here

See WXP Repair install procedure by michael stevens, read carefully

Alternatives, but you will lose all data on hard drive(s) are:

If Dell installed PC Restore by Symantec (DSR) utility on your PC & it still works (using Ctrl + F11 keys during boot) it will restore your PC to out-of-box condition. DSR is automatic (no need for CDs) & only takes 10 minutes

(even if you do have DSR, you should still request WXP CD)

Do a WXP Clean install but also requires reinstalling PC system drivers, post back if you require clarification