I would expect more and more sites to start following the trend, but up for pre-order right now on Walmart.com is the upcoming G.I. Joe: A Real American Hero Season 1 Part 1 DVD set from Shout! Factory. These DVD sets promise to hopefully finally get the entire Sunbow series out on DVD and available in mass markets for fans (new and old) to purchase.
Thanks to thunderdan19 of HissTank.com for the info!