Is the problem delivery of TigerDirect readers directly related to people not in U.S.? Because I got my $99 Reader from them four days after I ordered.
As for a law regarding prices, I don't know if it's LAW but I do know that most stores here in Colorado honor the lower price even if it's a mistake.
I know this personally because when I was in college I was a "Universal Product Code" specialist at a superstore. I basically just scooted around with a portable price sticker printer and a laser gun thingy and I put the UPC prices on products. I made a mistake and put a low price on an item and my manager wasn't pleased at all.
We had to honor the incorrect sticker price and he went to great lengths to make me understand that this was not the ideal way for me to move up in the organization.