I actually emailed REI about this, and they responded by directing me to something from Outdoor Products. NOT what I was looking for.

In any case, here's a couple of pictures of my 8x10 set up in what is basically the "Holden" configuration from the tarp PDF here. This is my favorite tarp configuration. The 8x10 doesn't have grommets at the middle of the long side, so I use a couple of plastic tarp clips to hold it up. The 9x12 has center grommets, but you need to raise the peak to about 6' in order to be able to close the wings fully. In the photo, the peak is at about 4.5'.

I like to use this setup for ARRL Field Day, along with my Byer Allagash cot, which fits underneath nicely. Since Field Day essentially means car camping, I can easily carry the cot (and a self-inflating mattress...very comfy).

The light green color is so much more pleasant than the typical blue tarp, and blends into the scenery better, as well.