I just picked mine up today from Best Buy for $29.99 before tax. There is a free Voltron T-shirt with purchase of any Voltron DVD set offer mentioned on Bestbuy.com. I was able to get the B&M store to give me the same deal, just by being polite and patient.
Also, I don't know if this is the same no matter where you buy it, but mine also included two extra DVDs. One was a preview disc for Tweeny Witches (the show) and the other was a trailer disc for Anime Works (the company).