So you need a computer that will allow you to configure the hardware raid and have enough slots for the array unless you are using a SAN – you were not clear in your question. If you are using a SAN you can connect that to your machine. I would recomend using Server 2003.
Once you have the array or san connected to your machine you will be able to boot to the controller card’s bios using Control – M or something like that. You will need to watch the bios screen until you see it spinning up the drives.
Then you can configure a Raid 0 if you want all your available space or raid 5 if you are looking for some fault tolerance. You will loose some space to the array though as it writes a small piece of all the data across all the drives so if one drive goes down you can continue working and trying to get back on line. In a Raid 0 you will be dead in the water if one drive dies.
Let me know what type of equipment you have and I can walk you through setting it up to specifications.