http://www.ebuyer.com/store/Componen...ives?refmen=tn Have a look here for internal and external hard disk drives; I find this site and
www.lambdatek.com is quite reliable and much cheaper than somewhere like maplins! If your computer is getting old and only has PATA interface, you can always ebay PATA to SATA interfaces which are v. cheap! Good luck!