The use of ice water in an experiment
1.With "salt", does Vogel mean just $\ce{NaCl}$?


Yep, it's cheap and available.


  
  How do I go about making these ice shards that are used in the lab?
  


Wrap the ice cubes in a towel and hit the bundle with a hammer until you get whatever size you want.  That's how we did it in the lab.