We have some for Lossless, but none for mp3 that I could find. Your ears might be you best bet for telling. 128 will always sound like 128, no matter what you do to it.
Tau Analyzer http://en.true-audio.com/Free_Downloads
There are some guys who convert 128kbps mp3 to 320kbps and say it's Extreme or Insane. There are some who make DD AC3 files from mp3.
Is there anyway or any tool to find if a sound is upscaled?