Check at 4am eastern time. The Apple refurbs seem to be restocked at that time. I know it sounds weird but Ive seen it first hand. Long time ago I was trying to get a nano for $99. They were constantly out. Someone here posted the 4am tip. I set alarm, got up right at 4, nothing. Refreshed a few times and by 10 after they were there.
Have also seen this "phenomenon" on other occasions with macbooks, ipod videos, and minis.