The closest I've seen to a Nforce with raid is the Gigabyte and maybe the MSI AMD flagship. however, I know that the MSI needs help from the serial raid to complete the volume. I think Gigabyte is the only board that has all the cool features.
Afrogeek, Gigabyte doesn't make an nForce or nForce2 board. I checked their website.
There are no nForce2 boards that support RAID, as far as I can tell. Besides, if they did it would most likely be two channels anyway, just like the vast majority of motherboards on the market. They won't be able to connect the number of devices you have.