Here are two reference sheets for computing Hom sets in derived categories, which you may find useful: 
    

 1. <a href="https://www.math.lsu.edu/~pramod/tc/ps/psqr.pdf">Perverse Sheaves Quick Reference Guide</a> and 
 2. <a href="https://www.math.lsu.edu/~pramod/tc/14s-7260/dercat.pdf">Derived Categories Cheat Sheet</a>.
    
Here are two more references: 

 1. <a href="https://www.math.lsu.edu/~pramod/tc/ps/psln.pdf">Applications of Homological Algebra</a> and
 2. <a href="http://arxiv.org/abs/math/0501094">Derived Categories of Sheaves: A Skimming</a>.