I have found 12:01 PM to buy on DVD!
After much searching I have managed to find 12:01 PM on DVD. It is part of a set comprising of other Oscar-winning/nominated short films. 12:01 PM is available either as part of an 8 film set on 1 DVD, or as part of the more extensive 56 film 7 disc set:
Cinema Collection: Vol. 5 (8 Films)
Link: http://www.play.com/play247.asp?page=title&r=R2&title=653519&p=57&g=72&pa=sr
Cinema Collection: Academy Award Winning Shorts Box Set (7 Discs)
Link: http://www.play.com/play247.asp?page=title&r=R2&title=741897&p=57&g=72&pa=sr
Just thought you'd all like to know! :D