This is from TV Guide's website today. In the meantime, I would definitely recommend watching the movie Fidel. This movie came out in 2002 and was directed by David Attwood and written by Stephen Tolkin. I am far from a history buff (so I don't know exactly how accurate it was), but I thought it gave a good picture of Cuba and how Fidel rose to power.
FIDEL FOUND: Oliver Stone's newly overhauled HBO documentary about Fidel Castro will finally see the light of day on April 14. According to The Hollywood Reporter, Looking for Fidel replaces an earlier version, titled Comandante, which apparently failed to address a recent crackdown on Cuban dissidents.