I have a desktop with Vista with raid mirroring.
I am going to do a clean install of Win 7.
Do I just go through the reformat step in the install normally? Is that all i need to do with raid?
If it is hardware raid, the disk will appear to Windows as just one standard disk and the raid card/chip will do all the "magic" for you!... You may need a disk with the raid drivers on during Windows setup. There is usually a feature in the BIOS, or raid utility that can generate this for you - or there may be a driver disk that came with the machine.
If it is software raid, the easiest thing to do is just set up Windows like normal on one disk and then convert the disks to dynamic and setup mirroring through disk management once all the installing is finished.