What is the model of the raid controller you're using and is it on-board or not?
The first thing is that you should NEVER use raid0 for an operating system disk and should hardly ever use raid0 at all. Despite that you're gaining a slight (and I mean slight b/c unless your card is seperate from the mobo and is true hardware raid...no cpu cycles for write divisions, XORs, etc.) speed boost in writing to two disks instead of one.
If you use raid0 on your machine with your operating system, be careful b/c a disk going pthththe means your system goes pthththe. If you're really concerned, get another disk, run that as the OS, and then raid1 the two sata disks for data. I could go on, but I don't wanna talk for hours.
TRY THIS:
There's a very good chance that you haven't created the array. Within the bios of your computer (or an external bios that boots up right after the mobo bios boots) you need to first create the array and let the bios know about it.
I don't mess with on-board raid, but boot up the machine and watch for anything raid. It will normally list the disks that're attached and customarily tell you to hit Ctrl-H to get into the bios. Once you're in, create the array (this sometimes takes a while depending on card, size of drives, etc.), reboot, THEN, install windows.
The reason you're not seeing the disk is b/c your raid controller doesn't know it has a legitimate storage unit on there. After you create the raid array in the bios, it will tell the mobo bios that there's a legitimate disk attached, and then your install should go along fine.
I hate to say this, but rtfm. A lot of the times manuals for computer parts that aren't customarily for the average user are horrible b/c they already assume some knowledge, but they always help.
Lemme know if that works for you b/c i can almost guarantee that's your problem.
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2 billion dollars...sir, I'd handle my grandpa's balls for 2 billion dollars.