I found it at Walmart a few months ago. Not the best quality in the world, but when I ran out and wanted more for a pillowcase, it was gone. And I can't find anything like it at Hancock or Joanns.I like it with the red Minnie dot - just wish my Walmart still had it.
I too have been looking for yellow polka dot. I found some with the gingham at Jo Ann's. I am making DD a sock monkey dress for the first day of school. I have everything cut out so I should go take a pic of the pieces.