Hi,
NXP does not provide stand alone programmers.
the colleague of mine prepared a document: S12(X) Programming/Debugging Possibilities
There is paragraph describing stand alone possibilities. Simply, it directs you to Pemicro.com or Lauterbach.com.
If you do not want to invest any money and there is only a few parts to be programmed it is also good to think about using CodeWarrior.
Best regards,
Ladislav