No Harddrive

I dont have an operating system or drive on my pc as it states.i had windows 2000 and me. i upgraded the me to xp but the xp doesnt work. when i tried booting the xp setup it siad that i had no drive of place for swap file. when you turn the pc on all it shows is a dell graphic unless you boot from a disk. when i boot from the xp boot disk the second one has an error. I want to install xp home but it says there are no drive to install on. my computer in a dell pc with an intel processor about six years old. It doesnt have an operating system installed or a c drive as it states. the only way it runs is if you boot it with a disk or cd. when i tried to install xp it said that my cp didnt have a drive to install on. i can give you more info if needed. thanks