ok, your setup is going to be a bit more complicated as i missed the "laptop" part. you wont have two hard drives but only a single hard drive partitioned into two. one will be for the backup files needed to restore your laptop in the event of an ubercrash, and in the absense of a vista cd. its your laptop makers doing it "on the cheap" and saving those extra few pennies it would cost to give you a cd copy of the operating system that you own.
you will need to ring whoever sold you the laptop and ask them to send you a copy of the operating system cd, which you can expect to pay anything up to £20 for. annoying i know, you've already bought the thing, but hey thats how low laptop manufacturers are stooping these days. its one of the reasons i went to linux on my laptop, i refuse to pay for the same thing twice.
as for an xp disc, they still come at a price. ebuyer is listing it as around £83
http://www.ebuyer.com/UK/product/114053
is it a hewlett packard laptop?