Wow, I'd never heard this before.....awesome piece!

I didn't find it terribly difficult, but of course I loved the piece.  It took a few months for me to really learn the first movement and memorize it.  It took another 3 months to learn and memorize the 2nd and 3rd movements. 

It's great to open a recital program or 2nd half of a recital program.  It allows the pianist to get very familiar with the piano right away as far as touch and sound production is concerned.

The pianist has to really sell the dualistic alternation between the harsh dissonances and the sentimental lyrical sections.  One has to bring out the main themes as they are usually not apparent to new listeners.

Aaron Copland dedicated the Piano Sonata to Clifford Odets. 

Odets is quoted as saying, "I would not be your true friend if I did not tell you here how beautiful the Sonata sounded on a third and fourth hearing...”

It's published by Boosey & Hawkes.  I have a link on my blog to purchase the score at musicnotes.com.  Just go to http://marioajero.blogspot.com and scroll all the way down to March 6, 2006.